ライフサイエンスコーパス: electron-donating

1 ples that stacking electrenes-a new class of electron-donating 2D materials-with other 2D materials p

2 annulene derivatives with various numbers of electron-donating 4-(N,N-dimethylamino)phenylethynyl (1-

3 he resulting nitrenium ion stabilized by the electron-donating 4-amino group yields the final cross-l

4 trated upon subsequent substitution with the electron-donating 4-methoxyphenoxy substituent.

5 Unsymmetrical cyclophanedienes comprising electron-donating (4-methoxy-1-(2-ethylhexyl)oxy)benzene

6 erein, we demonstrate that, depending on the electron-donating abilities (Lewis basicity) of anions a

7 In aprotic solvents, electron-donating abilities of anions generally follow t

8 ugh surface polarisation despite its poorest electron donating ability.

9 role in both the electron-accepting and the electron-donating ability of acceptor moieties with sulf

10 y in response to the electron-withdrawing or electron-donating ability of substituents positioned rem

11 he Ru(V)-oxo fragment is easily tuned by the electron-donating ability of the distal pyridyl ligand s

12 The electron-donating ability of the nonbonding HOMO is ther

13 By changing the electron-donating ability of the organic functional grou

14 The strong electron-donating ability of ZnTTFP was further enhanced

15 f the phenols is due to an increase of their electron-donating ability upon deprotonation and to thei

16 g of the chromophore with Tyr203 reduces its electron-donating ability, which can be restored by hali

17 eir exotic properties, such as extraordinary electron-donating ability.

18 e specific reactive intermediates by placing electron-donating/accepting residues nearby.

19 dentity of the initiating alkoxide with more electron-donating alkoxides resulting in faster polymeri

20 The regioselectivity is controlled by the electron-donating alkoxy group, whereas diastereo- and e

21 The presence of electron-donating alkyl groups leads to isomerization of

22 nation reveal that complexes containing more-electron-donating amido groups react faster than those w

23 ido groups react faster than those with less-electron-donating amido groups, and complexes containing

24 alyzed cross coupling reaction to install an electron donating amine group.

25 g alcohol, carboxylic acid, or amine when an electron-donating amino group is at the meta position, a

26 We have found that introduction of multiple electron-donating amino groups onto a simple o-(phenylaz

27 ligand, which can be suppressed by appending electron-donating amino substituents to the phthalocyani

28 sport upon n-doping, and optical response to electron-donating analytes.

29 Complexes ligated by more-electron-donating ancillary NHC ligands undergo reductiv

30 stulates that radicals substituted with both electron donating and accepting groups enjoy a special e

31 Identifying electron donating and accepting moieties is crucial to u

32 the MCD C-term signs from the corresponding electron donating and accepting orbitals.

33 with a D-pi-A-pi-D motif, where D and A are electron donating and accepting units, is observed in re

34 Electron donating and electron withdrawing ortho-substit

35 n of 4-substituted PNP cobalt catalysts with electron donating and sterically blocking methyl and pyr

36 erredoxin shows a short distance between the electron-donating and -accepting cofactors.

37 y amphoteric redox behavior with both strong electron-donating and -accepting potency.

38 tuned by varying the conjugation length and electron-donating and -accepting substituents on the bac

39 , utilizing designed terpyridines possessing electron-donating and -withdrawing aromatic residues for

40 11, depending on the substitution pattern of electron-donating and -withdrawing functionalities.

41 2-Phenylpyridines containing electron-donating and -withdrawing groups appear to be w

42 ted benzaldehyde derivatives with a range of electron-donating and -withdrawing groups as well as bra

43 push-pull sensor was prepared installing the electron-donating and -withdrawing groups through a mult

44 as proven to be compatible with a variety of electron-donating and -withdrawing groups, halogens, and

45 -disubstitution patterns spanning a range of electron-donating and -withdrawing propensities.

46 ) and LG with functional groups of differing electron-donating and -withdrawing properties.

47 rotocol is compatible with a wide variety of electron-donating and -withdrawing substituents and allo

48 lustrated with arenes and alkenes containing electron-donating and -withdrawing substituents resultin

49 proximal conformation is preferred when R is electron-donating and a distal one is favored when R is

50 The reaction yield is high for both the electron-donating and electron withdrawing substituents

51 the transfer of charge between complementary electron-donating and electron-accepting clusters in sol

52 The use of polymers based on alternating electron-donating and electron-accepting units not only

53 series of push-pull BODIPYs bearing multiple electron-donating and electron-acceptor groups were synt

54 The electron-donating and electron-releasing properties of t

55 In this paper, 23 substituents with various electron-donating and electron-withdrawing characters we

56 scope of 3-diazooxindoles and styrenes with electron-donating and electron-withdrawing groups and wo

57 found to be suitable for substrates bearing electron-donating and electron-withdrawing groups on the

58 This process is tolerant of electron-donating and electron-withdrawing groups on the

59 The reaction conditions tolerated neutral, electron-donating and electron-withdrawing groups presen

60 ligoamides were rationally functionalized by electron-donating and electron-withdrawing groups to aff

61 ronpa2, using amber suppression to introduce electron-donating and electron-withdrawing groups to the

62 pi-D2, and D1-A1-A2-D2, bearing a variety of electron-donating and electron-withdrawing groups, were

63 ange of aryl-substituted alkynyl ethers with electron-donating and electron-withdrawing groups.

64 Both electron-donating and electron-withdrawing substituents

65 nt both at positions 1 and 2; i.e., strongly electron-donating and electron-withdrawing substituents

66 s, heteroatom substitutions, and a series of electron-donating and electron-withdrawing substituents.

67 s nonlinear, with a small negative slope for electron-donating and weakly electron-accepting substitu

68 s such as molecular symmetry and strength of electron-donating and/or -withdrawing termini have on op

69 eal that when the proton donors D (which are electron-donating) and the proton acceptors A (which are

70 patible with the presence of halogen, alkyl, electron-donating, and electron-withdrawing substituents

71 ne alcohols containing electron-withdrawing, electron-donating, and sterically demanding substrate co

72 portion were either electron-withdrawing or electron-donating, and their influence on the photostabi

73 road range of thiols and azetidinols bearing electron-donating aromatics are successful, proceeding v

74 s of these redox events; phlorins containing electron-donating aryl groups are easier to oxidize and

75 gands were faster for complexes bearing less electron-donating bipyridines than for complexes bearing

76 bipyridines than for complexes bearing more electron-donating bipyridines.

77 how that by employing the bulky and strongly electron-donating boryl ligand (HCDippN)2B (Dipp, 2,6-(i

78 withCC5H4N), although attempts to introduce electron-donating (C6H4CH3, C6H4OCH3, C6H4Si(CH3)3) subs

79 The electron donating capability of the substituent also con

80 In this work, the electron donating capacities (EDCs) of terrestrial and a

81 hemical oxidation to quantify changes in the electron donating capacities (EDCs), and hence the redox

82 ed by A365 nm) and decreased with increasing electron donating capacities of the samples, thus exhibi

83 aused photooxidation, as shown by decreasing electron donating capacities.

84 aromaticity, apparent molecular weight, and electron donating capacity (EDC) of DOM with large chang

85 ool to determine the redox properties (i.e., electron donating capacity (EDC), electron accepting cap

86 y with antioxidant activity (a surrogate for electron donating capacity) for the collected samples, w

87 As the electron-donating capacity at the aromatic ring increase

88 The electron-donating capacity of HAs sorbed at Al(2)O(3) in

89 Conductivity but not electron-donating capacity was positively correlated wit

90 maticity (decreased SUVA-254), decreased DOM electron-donating capacity, and decreased DOM average mo

91 into CMPs during polymer synthesis affected electron-donating capacity, while carbonization of CMPs

92 It is revealed that copolymerizing electron-donating carbazole unit into the poly(9,9-dioct

93 involve the anionic ligands and the strongly electron donating carbene groups and (2) dipolar effects

94 ene/phthalocyanine, pinpointing the uncommon electron donating character of graphene.

95 om preferably bonds to electrophiles and its electron-donating character is markedly enhanced by effi

96 lopropane increases with the increase of the electron-donating character of (hetero)aromatic group at

97 rption behavior is attributed to the greater electron-donating character of the mu-OH(-) ligands and

98 the catalytic rates reach a maximum when the electron-donating character of X results in the pKa of t

99 pting ability and nitrogen affording greater electron-donating character.

100 ifferent aromatic aldehydes: one with strong electron-donating characteristics and one with strong el

101 azole electron-deficiency compensates alkoxy electron-donating characteristics, thereby lowering the

102 gy of 18.0 kcal/mol is observed for the most electron-donating combination of NMe(2) as the C-substit

103 nzo[1,2-b:4,5-b']di(cyclopenta-dithiophen e) electron-donating core and 1,1-dicyanomethylene-3-indano

104 with a larger pi-conjugation and a stronger electron-donating core shows a higher lowest unoccupied

105 c study showed that electron-withdrawing and electron-donating core substituents affect the rate-dete

106 were replaced in one step and high yield by electron-donating cyclic amines (pyrrolidine (TPMA(PYR)

107 a variable pi-conjugated spacer between the electron-donating (D) and electron-accepting (A) groups

108 Interfaces between organic electron-donating (D) and electron-accepting (A) materia

109 lls usually utilise a heterojunction between electron-donating (D) and electron-accepting (A) materia

110 The interface between electron-donating (D) and electron-accepting (A) materia

111 omising reactivity of the title compounds as electron-donating dienes.

112 The complex with the most electron-donating dithiolene ligand exhibits the highest

113 4) TCNQ) and decreasing conductivity for the electron-donating dopant benzyl viologen.

114 scence characteristics vary as a function of electron donating (EDG) and/or withdrawing (EWG) substit

115 discrete methoxyheteroarenium salts bearing electron-donating, electron-withdrawing, alkyl, aryl, ha

116 Salicylaldehydes bearing electron-donating, electron-withdrawing, and halogen gro

117 t-coordination sphere amino acids as well as electron-donating/electron-withdrawing substituents on t

118 find that MoS2 functionalized with the most electron donating functional group (p-(CH3CH2)2NPh-MoS2)

119 Overall, electron-donating functionalities are observed to increa

120 idinophanes in the literature are limited to electron-donating functionalities.

121 incorporating extended conjugation into the electron-donating fused-ring units in nonfullerene accep

122 The results reveal that the electron donating group at the meso position of BODIPY b

123 l AIE, diphenylamino (DPA) group as a strong electron donating group to benefit red emission and effi

124 etail, we chose catechols carrying either an electron-donating group (EDG) or an electron-withdrawing

125 the MediaChrom bearing a diethylamino as an electron-donating group and a trifluoromethyl as an elec

126 t yield, while substituted aryl ketones with electron-donating group and electron-rich heteroaromatic

127 is achieved when one phenyl ring carries an electron-donating group and the other one is substituted

128 teroaryl amides with benzyl chlorides having electron-donating group at para-position is reported.

129 umarin-IPP derivatives can be fine-tuned: an electron-donating group at PPh(3) enhances absorption an

130 roup in the equatorial phenyl ring and/or an electron-donating group in the axial ring has the lower

131 Again, introduction of an electron-donating group in the chromeno[3,4-c]chromene-6

132 from selective electron transmission from an electron-donating group to the meta and ortho sites on a

133 ted indoles and N-protected indoles with the electron-donating group with the former substrate being

134 push-pull derivatives bearing triphenylamine electron-donating group, cyclopenta[c]thiophen-4,6-dione

135 ead, the ruthenium catalyst acts as a strong electron-donating group, thus directing a remote electro

136 Aldehydes with electron donating groups at para and ortho positions are

137 Our data revealed that substitution of electron donating groups at the para-position on the phe

138 It is known that electron donating groups have quite a different effect o

139 ntents suggesting phenolic moieties as major electron donating groups in HS.

140 a preference for o- over p-substitution for electron donating groups, with both favored over m-addit

141 ying electron-withdrawing (50-85%) or weakly electron-donating groups (31-73%); cyclic aliphatic subs

142 ith different para substituents ranging from electron-donating groups (e.g., methoxy) to electron-wit

143 opyrans (12-74% yield), while those carrying electron-donating groups (EDGs) (Esigma < -0.31) gave fl

144 rawing groups (EWGs) and negative values for electron-donating groups (EDGs).

145 In contrast, the presence of electron-donating groups (OMe) on the nonfused Ar ring i

146 on of the phenol substrate and decrease when electron-donating groups are employed.

147 mide) (H4L1), and its derivatives containing electron-donating groups at the aromatic ring have been

148 e presence of either electron-withdrawing or electron-donating groups at the aromatic ring of the 2-a

149 Aryl substitution with electron-donating groups at the para position (e.g., the

150 pinel oxide B, both electron-withdrawing and electron-donating groups bearing phenols gave monohaloge

151 ields, and half-lives, and found that strong electron-donating groups enhance the reactivity toward h

152 l outcome of the reaction, complexes bearing electron-donating groups exhibited a higher catalytic ac

153 Substitution of the pyrazinium salts with electron-donating groups favors the formation of the 1,2

154 atic substituents and very weak influence of electron-donating groups have been established.

155 stabilisation of transition states featuring electron-donating groups in either ortho or para positio

156 The presence of strong electron-donating groups in the phenyl ring reveals to b

157 ound to increase the initiation rates, while electron-donating groups lead to slower precatalyst acti

158 Electron-donating groups on the fused aromatic ring (Y a

159 Employment of clusters with electron-donating groups or H(*) donors from thiols lead

160 d strength is unchanged by substitution with electron-donating groups or withdrawing groups or with i

161 position as major products, while those with electron-donating groups preferably yield indole product

162 Electron-donating groups slow down the reaction rate and

163 henyl ring cause higher quantum yield, while electron-donating groups such as amides and alkyl groups

164 The position of chiral and methoxy electron-donating groups within a trityl skeleton affect

165 roarenes, including arene substrates bearing electron-donating groups, bulky ortho functionalities, b

166 iodoarenes bearing electron-withdrawing and electron-donating groups, giving rise to different class

167 s substituents (electron-withdrawing groups, electron-donating groups, increased steric bulk, heteroc

168 f the respective nitroxides in comparison to electron-donating groups.

169 have been extended to benzyl esters without electron-donating groups.

170 ntum chemical calculations, the influence of electron-donating heteroatomic groups (O, NH) was invest

171 reduced steric hindrance and/or insertion of electron-donating hydroxyl groups in the N,N-dimethylami

172 igated, comparatively little is known on the electron donating (i.e., antioxidant) properties of HS u

173 of any substitutent (electron withdrawing or electron donating) in the 3-phenyl moiety.

174 In the presence of a high number of electron-donating iodide anions as parts of quaternary a

175 an asymmetric ligand that places a strongly electron-donating ligand trans to the site of CO(2) bind

176 of complexes 1 and 3 serves as the stronger electron-donating ligand, compared to thiolate, to reduc

177 Here, we show that the axial coordination of electron-donating ligands to active MOF-installed Fe-por

178 vable for compounds with sufficiently strong electron-donating ligands, and in digold complexes this

179 on dithiolate complexes bearing carbonyl and electron-donating ligands, the metal-metal bond is the h

180 :2',3'-c]phenazine (HATN-6CHO) and the first electron-donating linker 2,2'-([2,2'-bithiophene]-5,5'-d

181 ut are more highly functionalized, including electron-donating methoxy groups in addition to substitu

182 ylethenes increases with the introduction of electron-donating methoxy groups in the phenyl moiety.

183 While a single electron-donating methoxy substituent para to the seleni

184 drawing fluoro, chloro, ester, and nitro and electron-donating methyl, methoxy, dimethoxy, benzyl eth

185 arkedly stimulated by the introduction of an electron-donating module, optimizing the balance of O2 s

186 The four reported dyes include electron-donating moieties (N,N-dibutylaniline and N,N-d

187 tor molecular architecture, in which various electron-donating moieties are connected to an electron-

188 short, strong vibronic coupling between the electron-donating N-arylcarbazoles and the electron-acce

189 t into the organic sublattice containing the electron-donating naphthalene species enabled the tuning

190 ara position is generally facilitated by the electron-donating nature of the hydroxyl group.

191 nation faster than complexes ligated by less-electron-donating NHC ligands.

192 The effects of a para substituent, as the electron-donating -OCH3 and -OtBu groups and the electro

193 t position 5 of the heterocyclic moiety with electron-donating (OH (1b), OCH3 (1c)) or electron-withd

194 dge was tuned by substituents with different electron donating or accepting character.

195 sses of nanocarbon materials hybridized with electron donating or electron accepting molecules have b

196 ctional groups on the aromatic ring (whether electron donating or electron withdrawing) and can be ex

197 can generally be understood in terms of the electron donating or withdrawing ability of the substitu

198 The electron donating or withdrawing effect of the periphera

199 nalized with organic phenyl rings containing electron donating or withdrawing groups.

200 The description of substituents as electron donating or withdrawing leads to a perceived do

201 Remarkably, the electron-donating or -withdrawing ability of the para-su

202 let states can be further tuned by employing electron-donating or -withdrawing groups on the azulene

203 The electron-donating or -withdrawing properties of the para

204 fluorobenzenes are well correlated with the electron-donating or -withdrawing properties of the subs

205 up substitution on the charged amine or with electron-donating or -withdrawing ring substituents disp

206 identical withMo(OC(CH3)(CF3)2)3] featuring electron-donating or -withdrawing substituents on the be

207 are characterized by the presence of either electron-donating or electron-withdrawing groups as subs

208 e the para position of the Ar group contains electron-donating or electron-withdrawing groups, with s

209 ituent group in the diazonium salt, that is, electron-donating or electron-withdrawing in the ortho,

210 The effect of either an electron-donating or electron-withdrawing substituent is

211 ion is compatible with substrates possessing electron-donating or electron-withdrawing substituents a

212 ogy is compatible with substrates possessing electron-donating or electron-withdrawing substituents a

213 hiafulvalene (TTF) can be tuned by attaching electron-donating or electron-withdrawing substituents.

214 luoroborate with benzyl chlorides possessing electron-donating or electron-withdrawing substituents.

215 with both a negatively charged and strongly electron-donating outer sphere nucleophile, result in th

216 Having electron donating p-methoxybenzyl ether (PMB) groups inc

217 (BHJ) layers of visible (VIS) light-sensing electron-donating (p-type) polymer and near infrared (NI

218 We discovered that the electron-donating P3HT and even inorganic materials, ind

219 in the environment results in a depletion of electron donating phenolic moieties with antioxidant pro

220 ic and electrochemical detection to quantify electron-donating phenolic moieties in DOM by determinin

221 ool of redox-active moieties is dominated by electron-donating, phenolic moieties in the low-HTT char

222 rboxylic acids and related butyl esters, and electron-donating phenyldodecyl ethers were synthesized.

223 ere employed, and the compound with the most electron-donating phosphine ligand and the most basic am

224 In aprotic, electron-donating, polar solvents., e.g., acetonitrile (

225 The conformation of the electron-donating polymer is significantly disrupted by

226 osed of an electron-accepting polymer and an electron-donating polymer remains limited.

227 bital energies and molecular ordering of the electron-donating polymer.

228 tter is governed by interactions between the electron-donating porphyrin and the electron-accepting f

229 2 is promoted by a combination of the strong electron donating power of C12A7:e(-), ability of Ru to

230 tants (k(f)) that decrease by increasing the electron donating power of the arylsulfinyl substituent

231 3) linkage can only marginally influence the electron donating power of the ligand.

232 reoelectronic profile: combination of strong electron-donating power (Tolman's electronic parameter 2

233 d as macrocyclic counterpart of PTA with the electron-donating power approaching that of strongest kn

234 regularly increase through a decrease in the electron-donating power of the aryl substituents, that i

235 ate constants was observed by increasing the electron-donating power of the arylsulfenyl substituent,

236 LFP experiments, decrease by increasing the electron-donating power of the arylsulfinyl Y substituen

237 ovalently linked nanoconjugates that feature electron-donating pressure synthesized carbon nanodots (

238 he most energetically favorable chemotrophic electron-donating process known.

239 r 4-Cl-aniline, and correlated well with the electron donating properties of the substituent.

240 6 and 7, despite the significantly different electron-donating properties associated with the o-CF(3)

241 electrochemical properties because of strong electron-donating properties of carbazole group.

242 The strong electron-donating properties of MTTFP were probed by ele

243 er O-H bond of 1, such as differences in the electron-donating properties of the ligand, metal ion Le

244 singlet spin state that correlates with the electron-donating property of the para-Z substituent, wh

245 ides, while poorly reactive nucleophiles and electron-donating protecting groups on the donor favor a

246 of one of the triazolate linkers with a more electron-donating pyrazolate group leads to the isostruc

247 wing pyridyl ("X") substituents, but also by electron-donating pyrazolyl ("Y") substituents.

248 (2)bpy)CuC(2)F(5)] complexes containing less electron-donating R(2)bpy ligands than to those containi

249 (2)bpy ligands than to those containing more electron-donating R(2)bpy ligands.

250 Based on the addition of a strongly electron-donating solvent, trimethyl phosphate (TMP), th

251 Donor groups are varied based on electron donating strength and sterics at the donor-pi b

252 ic HER are both directly correlated with the electron donating strength of the functional group.

253 as demonstrated by a red shift following the electron-donating strength of the appended aromatic moie

254 ligand charge transfer (ICT) with increasing electron-donating strength of the aryl ligand.

255 Employing an electron-donating substituent (R = NMe2) results in a lo

256 In the case of benzoates carrying an electron-donating substituent the experimental findings

257 below 20 kcal mol(-1) and is accelerated by electron donating substituents on the aromatic ring, whi

258 Reductive elimination is accelerated by electron-donating substituents (rho = -2.0) on one or bo

259 nds show that the kinetic selectivity favors electron-donating substituents and correlates well with

260 ntrary to the expectation, it was found that electron-donating substituents are preferable, in partic

261 analogues were designed bearing hydrophobic, electron-donating substituents at the para position of t

262 Electron-donating substituents at the pyridine improve t

263 Diarylviologens containing electron-donating substituents complexed with cucurbit[8

264 nformational energy of the aryl group, while electron-donating substituents increase the conformation

265 dimerization equilibrium constant, with para electron-donating substituents leading to a weaker bond

266 s) exhibits strong substituent effects, with electron-donating substituents markedly decreasing condu

267 electron-withdrawing, electron-neutral, and electron-donating substituents on both coupling partners

268 nt for various aromatic rings indicates that electron-donating substituents on the benzyl groups acce

269 We find that these electron-donating substituents on the phenyl ring have l

270 erates a variety of electron-withdrawing and electron-donating substituents on the substrates.

271 When styrenes with electron-donating substituents or disubstituted were emp

272 with both strongly electron-withdrawing and electron-donating substituents shown to significantly re

273 e compounds bearing electron-withdrawing and electron-donating substituents synthesized by alkyne cou

274 Compounds with greater amine charge/area and electron-donating substituents that allowed for greater

275 in the radical cation species with strongly electron-donating substituents that yields a less electr

276 xpected ability of arylzinc reagents bearing electron-donating substituents to react in a Friedel-Cra

277 ternal alkynes with electron-withdrawing and electron-donating substituents were tolerated.

278 oxidation are enhanced by substitution with electron-donating substituents, such as the S-atom in ph

279 T) leads to a shift of electron density from electron-donating substituents, which is readily observa

280 on of 2:2 quaternary complexes is favored by electron-donating substituents, while electron-withdrawi

281 wo external rings by electron-withdrawing or electron-donating substituents.

282 ocyanates give better results when they bear electron-donating substituents.

283 romatic groups with electron-withdrawing and electron-donating substituents.

284 re much higher, but only for substrates with electron-donating substituents.

285 eraction whenever the carbonyl group carries electron-donating substitutents, specifically for ureas,

286 parately to sewage sludge which provided the electron-donating substrate and at prescribed time point

287 Use of an electron-donating sulfonyl group results in an unanticip

288 The anionic, electron-donating thiocatecholato motif provides an exce

289 ased upon substitution of the TAPP core with electron-donating thiophene units, the extent of which i

290 xanones, with para-substituents ranging from electron-donating to electron-withdrawing, were reacted

291 CH3, OCH3, Cl, CN, and NO2) that ranged from electron-donating to electron-withdrawing.

292 its and di(tert-butyl)carbazole (DTC) as the electron-donating units.

293 When the aromatic rings are modified with electron donating (withdrawing) groups, the reducing pow

294 inds of substitution, including alkyl, aryl (electron-donating, -withdrawing, and -neutral), heteroar

295 Tuning electron donating/withdrawing capability of the carbon b

296 substituents on the alkyne units, including electron-donating/withdrawing aryl groups, silyl-protect

297 o shift the methyl signal downfield, whereas electron-donating X-groups cause a more upfield shift.

298 N-substituent of the NHC ligand presents an electron-donating Y group.

299 This conclusion suggests that electron-donating Y groups could stabilize higher oxidat

300 the complexes before oxidation suggests that electron-donating Y groups destabilize the metal centere