ライフサイエンスコーパス: addition reaction

1 anhydride) chain via a one-step nucleophilic addition reaction.

2 AP) is the enzyme that catalyzes the poly(A) addition reaction.

3 uminate the molecular basis for the fumarate addition reaction.

4 utive formation of two C-C bonds in a single addition reaction.

5 -2-azido-(1->2) thiodisaccharides through an addition reaction.

6 tion, Curtius rearrangement and nucleophilic addition reaction.

7 the high temperatures needed to promote the addition reaction.

8 ng tetrasubstituted ones, in a "C(2) + N(1)" addition reaction.

9 lt-maleic anhydride), PIMA, via nucleophilic addition reaction.

10 enantiofacial selectivity in the dialkylzinc addition reaction.

11 ntal to the enantioselectivity of asymmetric addition reaction.

12 quaternary stereogenic centers via the aldol addition reaction.

13 ) rapidly react with GSH and Cys via Michael addition reaction.

14 the sense of stereoinduction observed in the addition reaction.

15 RNA, with efficiency comparable to the G(-1) addition reaction.

16 tions and also regulate the de novo telomere addition reaction.

17 e 2 (TUTase 2; RET2) catalyzes the uridylate addition reaction.

18 cation sites by the beta-elimination/Michael addition reaction.

19 type coupling as well as an enantioselective addition reaction.

20 -Pr)(3)](2), is not active in the asymmetric addition reaction.

21 at the methylene carbon during the oxidative-addition reaction.

22 a a tandem cyclic N-acyliminium nucleophilic addition reaction.

23 cetonitrile hexafluorophosphate catalyze the addition reaction.

24 this may be a previously unsuspected generic addition reaction.

25 crosslinker (CGPQG IWGQC) via a Michael-type addition reaction.

26 d to rationalize the regioselectivity of the addition reaction.

27 g-pong mechanisms to catalyze the amino acid addition reaction.

28 nstead of the commonly proposed nucleophilic addition reaction.

29 cysteine-316 in alpha-tubulin via a Michael addition reaction.

30 Pd-catalyzed hydrogenation or thiol-mediated addition reaction.

31 involved a 6-exo-trig free-radical conjugate addition reaction.

32 's catalytic Cys115 residue by a Michael 1,4-addition reaction.

33 ficient and enantioselective boryl and silyl addition reactions.

34 enantioselective nickel-catalyzed conjugate addition reactions.

35 ymmetric quimioselective aldol and conjugate addition reactions.

36 olymerization through their efficient alkyne addition reactions.

37 ies in copper-catalyzed asymmetric conjugate addition reactions.

38 nt from that used previously for other boron addition reactions.

39 moieties in organic matter via nucleophilic addition reactions.

40 e classical reactivity pattern for conjugate addition reactions.

41 he development of Lewis base catalyzed aldol addition reactions.

42 xample of Bronsted acid catalysis in radical addition reactions.

43 m N-acyliminium ion cyclization-nucleophilic addition reactions.

44 ts noncanonical participation in bimolecular addition reactions.

45 o elusive tetrahedral intermediates of amide addition reactions.

46 s or can be used in stereoselective carbonyl addition reactions.

47 roxides, or that promote nucleophilic halide addition reactions.

48 erved that appear to be the result of oxygen addition reactions.

49 vity of chiral lithium amide-induced enolate addition reactions.

50 a variety of nucleophilic and electrophilic addition reactions.

51 ation reaction, and hydrogen abstraction and addition reactions.

52 ant methods to execute robust carbonyl anion addition reactions.

53 nd expanding the generality of these Michael addition reactions.

54 used to guarantee good results in conjugate addition reactions.

55 hoxyphenyl (PMP) in the Lewis acid-catalyzed addition reactions.

56 r to enals, enones, and enoates in conjugate addition reactions.

57 ndergoes tandem electrophile/nucleophile 1,4-addition reactions.

58 ng Julia olefination and methyl ketone aldol addition reactions.

59 s previously shown to catalyze both of these addition reactions.

60 lyzed [4 + 1]-cycloaddition with aza-Michael addition reactions.

61 Xaa-NH2-type peptidic catalysts in conjugate addition reactions.

62 the scope of potential donors for conjugate addition reactions.

63 ydrogen atom transfer to alkenes and Minisci addition reactions.

64 n that complements a wide range of conjugate addition reactions(1-5).

65 -CF3 and C-C or C-heteroatom bonds by formal addition reactions across pi-systems, as such difunction

66 hydrocarbon whose reactivity is dominated by addition reactions across the central inverted bond to p

67 Cys can be easily labeled in a nucleophilic addition reaction after separation by reverse-phase C18

68 nd even carbon nucleophiles, can be used for addition reactions after tethering them to enol ethers.

69 nchona alkaloid-urea catalyzed sulfa-Michael addition reactions, also applies to the catalytic system

70 An intermolecular Michael addition reaction and an intramolecular condensation wer

71 r was found to be activated by the ubiquitin-addition reaction and blocked by the ubiquitin-removal r

72 tereoselective heteroatom-directed conjugate addition reaction and cyclopentanone ring cyclization as

73 (CN(-)) based on a Michael-type nucleophilic addition reaction and intramolecular charge transfer (IC

74 rophosphate release completes the nucleotide addition reaction and is associated with extensive confo

75 t a good understanding of the hetero-Michael addition reaction and the relative reactivities of biolo

76 on equivalents in Lewis base catalysed aldol addition reactions and allow for the preparation of cros

77 ining a cis-enone are susceptible to Michael addition reactions and are potent inhibitors of several

78 e Pd(CNAr(Dipp2))(2) is active for oxidative addition reactions and readily reacts with benzyl chlori

79 ons likely feature silyl radicals undergoing addition reactions and SH 2 reactions.

80 issions followed by hydrogenation, gas phase addition reaction, and/or partial oxidation.

81 sequential inter/intramolecular substitution-addition reactions, and in some cases, ring rearrangemen

82 anchoring chemical functions via the Michael addition reaction; and (iii) PDOPA was used as a reactiv

83 Copper-catalyzed asymmetric conjugate addition reactions are a very powerful and widely applie

84 rogen abstraction reactions and the hydrogen addition reactions are calculated.

85 the catalytic and stoichiometric asymmetric addition reactions are different, indicating that the pr

86 analyses suggest that such photonucleophilic addition reactions are reversible, with more rapid elimi

87 function as a dipole in a 1,3 dipolar cyclo-addition reaction as the initial step in a novel type of

88 reaction and an intermolecular nucleophilic addition reaction as the key steps.

89 vorable conditions for PAHs by the gas-phase addition reaction at a relatively low temperature compar

90 h we propose occurs via an in situ oxidative addition reaction at the Au surface.

91 azide complex 10 undergoes a Zr(+)/P FLP N,N-addition reaction at the terminal azide nitrogen atom to

92 introduced; these boryl and silyl conjugate addition reactions (BCA and SCA, respectively), which pr

93 roduct of this stereoselective rearrangement-addition reaction, beta-oxyalkenylbenziodoxole, represen

94 cyclized through a proximity-driven Michael addition reaction between a cysteine and an amber-codon-

95 The bimolecular rate constants of the addition reaction between hydroxyl radical (*OH) and nit

96 s-cinchona catalyst 3b activates the Michael addition reaction between malononitrile derivatives 2 an

97 As an example the organocatalysed Michael addition reaction between nitrostyrene and 3-methoxy-dim

98 ands are built using a one-step nucleophilic addition reaction between poly(isobutylene-alt-maleic an

99 A reversible Michael addition reaction between thiol nucleophiles and cyanoen

100 unsaturated carboxylic acid derivatives: The addition reactions between achiral Ni(II)-complex of the

101 In this work, cross silyl benzoin addition reactions between acylsilanes (1) and aldehydes

102 The insights enabled conjugate addition reactions between aldehydes and nitroolefins on

103 ng the stereochemical outcome of the Michael addition reactions between nucleophilic glycine equivale

104 This paper describes a systematic study of addition reactions between the chiral Ni(II) complex of

105 ereoselectivity in the corresponding Michael addition reactions between the Ni(II) complex of glycine

106 his understanding, such as kinetics of thiol addition reactions, bioactivities, as well as steric and

107 also found to be useful in the dimethylzinc addition reaction, both catalyzing the addition to benza

108 ed in the titanium-mediated asymmetric aldol addition reaction by treatment with titanium tetrachlori

109 be activated toward highly enantioselective addition reactions by (salen)metal catalysts to an impor

110 in a tandem cycloisomerization/nucleophilic addition reaction, by attaining high enantioselectivity

111 The addition reaction can be reversed by CO reduction of [Au

112 hanism of the enantioselective sulfa-Michael addition reaction catalyzed by a cinchona alkaloid-squar

113 y in eukarya via an unusual 3'-5' nucleotide addition reaction catalyzed by the tRNA(His) guanylyltra

114 The guanine nucleotide addition reaction catalyzed by Thg1 extends the polynucl

115 pport a general mechanism for the amino acid addition reaction catalyzed by this class of enzyme.

116 The atom transfer radical addition reaction catalyzed by triphenylphosphine and co

117 The fumarate addition reaction, catalyzed by the enzyme benzylsuccina

118 relevance to reductive elimination/oxidation addition reaction chemistry of transition metal catalyst

119 Nucleophilic addition reactions compete with two electron reduction o

120 In addition, reaction conditions that facilitate catalyst r

121 These addition reactions create up to two stereogenic centers,

122 Suzuki, Heck, Kumada, and Negishi couplings, addition reactions, cycloadditions, C-H functionalizatio

123 on to catalytic activity in a Friedel-Crafts addition reaction, data demonstrate that (31)P NMR shift

124 This regioselective alkyl radical addition reaction does not require metals, ligands or ad

125 ed to the high regioselectivity in the Prato addition reaction driven by the strain release of the Gd

126 nsation, Mannich, oxidation, and aza-Michael addition reactions, employing a variety of functionalize

127 broad functional group compatibility of this addition reaction enable substitution patterns that are

128 The initial addition reaction follows a stepwise diradical pathway t

129 e have compared the mechanism of the alcohol addition reaction for the enyne with that of the enyne w

130 The net electrophilic addition reactions formally require 2e(-) oxidation of t

131 Study of the intramolecular aza-Michael addition reaction from an aminofluorovinylsulfone opens

132 catalyzed asymmetric guanidine aza-conjugate addition reaction has been developed.

133 The beta-elimination/Michael addition reaction has been employed for the modification

134 The initial addition reaction has to overcome an energy barrier of a

135 eral activator of organotrimethylsilanes for addition reactions has been established.

136 mediated, enantioselective vinylogous aldol addition reactions has been investigated.

137 oundations of the Lewis base catalyzed aldol addition reactions have been investigated.

138 ark publications of the first directed aldol addition reaction in 1973, the site, diastereo-, and ena

139 one can be efficiently combined to a Michael addition reaction in a new two-step domino reaction, all

140 cyclohexane-1,2-diamine]Br(2), catalyzed the addition reaction in the presence of water.

141 Ligand 3f was found to catalyze this addition reaction in up to 76% ee.

142 t more widespread roles for 3'-5' nucleotide addition reactions in biology than previously expected.

143 ion chemistry stemming from condensation and addition reactions in OA formed by photooxidation of iso

144 both green mechanochromism and load-induced addition reactions in solution and solid.

145 )](2-) are excellent participants in Michael addition reactions in the presence of a strong acid.

146 different branching ratios for the OH and Cl addition reactions in the presence of NOx.

147 esultant enynals participate in a variety of addition reactions including aldol condensations and rea

148 uced indirect trapping of the retroconjugate addition reaction intermediate involved in the epimeriza

149 amma ligand binding domain through a Michael addition reaction involving a protein cysteine residue a

150 ergo a highly regio- and stereoselective 1,2-addition reaction involving protonation of an ortho carb

151 tereoselectivity observed in the diethylzinc addition reaction involving regioisomeric, pseudo-enanti

152 The activation enthalpy of the reverse addition reaction is also subject to structural variatio

153 The quinone addition reaction is characterized by excellent chemosel

154 ta confirm that the disiloxanediol-catalyzed addition reaction is first order in catalyst over all co

155 These correlations revealed the thiol addition reaction is primarily sensitive to the electron

156 mechanism detailing the observed cyclization/addition reaction is proposed.

157 NMR experiments indicate that the addition reaction is reversible under acidic conditions.

158 ditions) on catalytic enantioselective silyl addition reactions is analyzed.

159 Addition reactions mainly of carba- and heteronucleophil

160 The oxidative addition reaction mechanism was studied using density fu

161 This Article demonstrates how nucleophilic addition reactions mediated by photoredox catalysis can

162 both intra- and intermolecular nucleophilic addition reactions mediated by strong Lewis acids, such

163 ve strategy for promoting biphilic oxidative addition reactions more typical of transition metals.

164 oelectronic effect that controls the type of addition reaction observed.

165 al, strongly suggesting that polymerization (addition reactions) occurs.

166 The subsequent addition reaction of 2 with the appropriate isocyanate p

167 elective [1 + 2] cycloaddition or a carbonyl addition reaction of a thermally generated pi-delocalize

168 screened as organocatalysts for the Michael addition reaction of aldehydes with beta-nitroalkenes at

169 has been developed via a tandem thio-Michael addition reaction of an in situ generated alpha,beta-uns

170 Five-component sequential Ugi/nucleophilic addition reaction of aromatic aldehydes, primary amines,

171 script, a simple and efficient sulfa-Michael addition reaction of aryl thiols to trisubstituted alpha

172 tudy the energetics and the mechanism of the addition reaction of borylenes to unsaturated CC bonds,

173 An efficient Michael addition reaction of differently substituted enones with

174 We report here the intermolecular metal-free addition reaction of functionalized benzyl halides to al

175 f 1 was confirmed by thiol-selective Michael addition reaction of immunoprecipitated CD43-myc/FLAG.

176 mmobilized anion-pi catalysts to explore the addition reaction of malonic acid half thioesters to eno

177 rnatively, 2 can be prepared by an oxidative-addition reaction of Mes(2)Si(H)OTf (Tf = CF(3)SO(3)) wi

178 The first example of a catalytic Michael addition reaction of non-activated aliphatic nitriles to

179 An intramolecular FeCl3-catalyzed Michael addition reaction of styrene, a poor nucleophile, onto a

180 The electrophilic addition reaction of sulfur monochloride and sulfur dich

181 r the unreported, enantioselective conjugate addition reaction of the barbituric acid pharmacaphore t

182 zed Leu66 side chain, suggesting a conjugate addition reaction of the imidazole nitrogen to the highl

183 ccinyl)cysteine (2SC) is formed by a Michael addition reaction of the Krebs cycle intermediate, fumar

184 Addition reactions of (TSPP)Rh-OH to unactivated termina

185 adings as low as 0.1 mol%, for the conjugate addition reactions of 1,3-dicarbonyl compounds to beta-n

186 ith the faster reactions of 2 in THF and the addition reactions of 2 to carbonyl compounds.

187 cetates, constructed from the Li-Br exchange/addition reactions of 2-vinylbenzaldehydes and 2-(but-3-

188 ssel has been utilized for catalytic Michael addition reactions of a series of nitrostyrene derivativ

189 ate the first irreversible step in oxidative addition reactions of a zerovalent nickel catalyst to a

190 The deborylative 1,2-addition reactions of alkyl 1,1-diborons proceed in the

191 eadily prepared from sequential 1,4- and 1,2-addition reactions of allyl and 3-substituted allylsilan

192 orthoplatinated triaryl phosphite-catalyzed addition reactions of arylboronic acids with aldehydes f

193 CuCl/bipyridine-catalyzed addition reactions of arylboroxines with aldehydes and a

194 microwave energy, CuCl/bipyridine-catalyzed addition reactions of arylboroxines with aldimines were

195 The addition reactions of borylenes to multiple C-C bonds ar

196 The title compound (1) undergoes 1,2-addition reactions of both electrophilic and nucleophili

197 (2)NCHO, indicating the presence of hydrogen-addition reactions of DNCO and HDNCO.

198 Catalyst-controlled divergent addition reactions of enoldiazoacetamides with nitrones

199 relief of pyramidalization strain, as in the addition reactions of fullerenes, presumably contributes

200 s of the regioisomers and thermodynamics for addition reactions of olefins with Rh-H and Rh-OH units

201 ion of developments for asymmetric conjugate addition reactions of organocopper reagents with nonrace

202 III) intermediate that has been proposed for addition reactions of organocopper(I) reagents and alpha

203 Oxa-Michael reactions, i.e. addition reactions of oxygen nucleophiles to conjugated

204 Addition reactions of perfluoroalkyl radicals to ordinar

205 es and palladium-catalyzed isomerization and addition reactions of propargylic acetates.

206 retical study is presented of several ligand addition reactions of the triplet fragments (3)Fe(CO)(4)

207 The conjugate addition reactions of trans-1,2-di(2-pyridyl)ethylene ha

208 Alkylation and conjugate addition reactions of trivalent phosphorus (P(III)) spec

209 In addition, reaction of (N4)Pd(II)Me(2) with cumene hydrop

210 In addition, reaction of 1 with (t)BuMe2SiCl results in the

211 In addition, reaction of plant RG lyase digestion products

212 In addition, reaction of tripyrrane 11 with acenaphthopyrro

213 In addition, reactions of NO(3) with biogenic hydrocarbons

214 Examples of addition reactions on the metal centre, B-H activation,

215 fined almost exclusively to substitution and addition reactions on the perimeters of the compounds ("

216 and beta-functionalization of carbonyls, and addition reactions onto double and triple bonds.

217 o not generally follow the rules that govern addition reactions or the making of pristine fullerenes.

218 studies have established that the oxidative addition reactions proceed by a dissociative mechanism.

219 In the latter method, the formal oxidative addition reaction produced ((iPr)PDI)FeBr (1-Br), along

220 both the desired glycoside (e.g., 9) and the addition-reaction product (e.g., the anomeric mixed acet

221 d (b) catalyzing the transformation from the addition-reaction product to the desired glycoside (e.g.

222 ols were racemic, most likely due to a rapid addition reaction promoted by LiX (X = Br and Cl).

223 d in highly enantioselective Diels-Alder and addition reactions, providing functionalized bicyclo[2.2

224 s, where they function in the critical G(-1) addition reaction required for tRNA(His) maturation.

225 ric compounds react with GT through a simple addition reaction resulting in formation of the carbinol

226 The first addition reaction results in the formation of a predomin

227 ones, sulfoxides, and esters in Michael-type addition reactions reveals, for the first time, that the

228 y initiating the cleavage reaction by Pb(2+) addition, reaction samples were automatically injected d

229 Finally, mechanistically related addition reactions such as ketone additions to imines (M

230 lso reacts more efficiently in electrophilic addition reactions such as those with sulfides.

231 ments were linked by a challenging conjugate addition reaction that also generated the C11 quaternary

232 d rate enhancement of the disfavored enolate addition reaction that coincides with an increase in sel

233 NA residues suggest an unfinished nucleotide-addition reaction that is likely at equilibrium between

234 ssential to this strategy is a novel radical addition reaction that permits the attachment of a fully

235 (*+) adduct may represent a general class of addition reactions that can form complex heterocyclic sp

236 trophilicity permits anion detection through addition reactions that disrupt dye conjugation.

237 vatives have proven valuable in coupling and addition reactions, the direct use of alcohols as synthe

238 t only electrostatically but also by Michael addition reaction to cysteine, lysine, or arginine funct

239 that will undergo an intramolecular Michael addition reaction to form two new stereogenic centers.

240 roxy intermediate can perform a nucleophilic addition reaction to the substrate, NOHA.

241 oes a second reductive elimination/oxidative addition reaction to yield isotopically labeled methane

242 shown to be effective radical precursors for addition reactions to alkenes when treated with tripheny

243 e or exceptionally highly regioselective 1,4-addition reactions to alpha,beta-gamma,delta-unsaturated

244 on mode is analogous to that of most thermal addition reactions to C70.

245 a method to expand the scope of nucleophilic addition reactions to carbon-carbon multiple bonds.

246 The Zr(+)/P pair 10 undergoes selective 1,4-addition reactions to conjugated enones and to a conjuga

247 Conjugate addition reactions to enones can now be done in water at

248 f reduction, cycloaddition, and nucleophilic addition reactions to form highly substituted azetidines

249 phosphoric acids for a range of nucleophilic addition reactions to imines and developed statistical m

250 r toward heterocumulenes, undergoing Zr(+)/P addition reactions to the carbonyl groups of an alkyl is

251 pha-disubstituted-beta-aminonitriles through addition reactions to the corresponding N-tert-butanesul

252 application of two methyl ketone boron aldol addition reactions to the latent C(7)-C(11) dialdehyde s

253 this subject has been demonstrated mainly in addition reactions to unsaturated carbon-carbon bonds, a

254 nd undergoes typical regioselective 1,2-Zr/B addition reactions to yield the metallaheterocyclic prod

255 The conjugate addition reactions used both acrylate and maleimide Mich

256 e application of an Evans Cu-catalyzed aldol addition reaction using a strained cyclopropyl ketenethi

257 attached at the 6-position via an oxidative addition reaction using I2.

258 attached at the 5-position via an oxidative addition reaction using iodine.

259 stitution has on thermally forbidden [2 + 2] addition reactions using high-level density functional t

260 bioinspired synthetic cage catalyzes Michael addition reactions using only Coulombic and other weak i

261 ] 2 via alkyl halide alkylations and Michael addition reactions was systematically studied as a gener

262 alytic performance in representative Michael addition reactions was used in an effort to compare the

263 rrhenius activation parameters for the aldol addition reaction were determined.

264 lues for pyruvate and aldehydes in the aldol addition reactions were affected </=10-fold in the doubl

265 ch metal complexes able to promote oxidative addition reactions where the redox changes are exclusive

266 This addition reaction which proceeds in mild and moderate di

267 cal enzyme family and catalyzes the fumarate addition reaction, which enables microorganisms to utili

268 These sulfite addition reactions, which are slowly reversible and are

269 uinonediimine participated in a Michael-type addition reaction with 2-SH-benzazoles and after intramo

270 ed p-quinone imine participates in a Michael addition reaction with 2-SH-benzazoles leading to the di

271 hown to undergo a new type of tandem radical addition reaction with alkynes that affords five-membere

272 d ketimines have been applied for asymmetric addition reaction with allylmagnesium bromide.

273 ted quinone diimine undergoes a Michael-type addition reaction with arylsulfinic acids to yield the r

274 ion surrogate in the DBU-catalyzed conjugate addition reaction with enones and enals for the synthesi

275 t presents the least steric obstacles to the addition reaction with methane yields the greatest energ

276 g of GSH in a GSH and GSSG mixture via a 1,4-addition reaction with p-benzoquinone (BQ), followed by

277 A 1,4-addition reaction with propynal coupled with Schiff base

278 e) undergoes tandem electrophile/nucleophile addition reactions with a high degree of regiocontrol de

279 , in most cases, diastereoselectivity of the addition reactions with a Ni(II) complex of the chiral S

280 rignard reagents examined gave exclusive 1,4-addition reactions with alpha,beta-gamma,delta-unsaturat

281 Thus, AA is subject to typical olefin-addition reactions with bromine, sulfuryl chloride, m-ch

282 systematic studies of arylcuprate conjugate addition reactions with cis and trans gamma-alkoxy-alpha

283 the nitro group, thus competent for Michael addition reactions with cysteine and histidine.

284 silylene species undergoes facile oxidative addition reactions with dihydrogen (at sub-ambient tempe

285 s as a very reactive nucleophilic carbene in addition reactions with five simple alkenes.

286 e resulting 2,3-dihydropyridones undergo 1,4-addition reactions with Grignard reagents in the presenc

287 aracter of the Si=As bond of A, it undergoes addition reactions with H(2) O and NH(3) , forming LZnAs

288 iomeric ratios are obtained in the conjugate addition reactions with methyl vinyl ketone while low en

289 ed spiropyrrolidines were synthesized by 1,4-addition reactions with nitroalkanes, followed by reduct

290 a,beta-Unsaturated ketones generally undergo addition reactions with nucleophiles with a preference f

291 N-carbamoyl-4-pyridones undergo conjugate addition reactions with organocuprates and organozincate

292 Catalytic asymmetric conjugate addition reactions with organometallic reagents are powe

293 ndergo intra- or intermolecular nucleophilic addition reactions with stabilized enolates, silyl keten

294 ch reactive aldehydes are subject to Michael addition reactions with the side chains of lysine, histi

295 structures studied rapidly underwent Michael addition reactions with the test nucleophile glutathione

296 cetylenedicarboxylate readily undergoing two addition reactions with thiolate nucleophiles and the (Z

297 her, HNO is predicted to principally undergo addition reactions with thiols and ferric proteins.

298 A host of sequential 1,2-addition reactions with various alkyl halides was discov

299 f Se-alkylselenocysteine followed by Michael addition reactions with various thiol nucleophiles gener

300 The second addition reaction, with enones, does not occur under our