ライフサイエンスコーパス: ylide

1 tropic rearrangement of an in situ generated ylide.

2 arrangement of a nitrile-stabilized ammonium ylide.

3 and by isolation of its trimethylphosphonium ylide.

4 ion present in the base used to generate the ylide.

5 aldehyde 19 with an amide-stabilized sulfur ylide.

6 e intramolecular syn-beta-elimination of the ylide.

7 ration that supports formation of a reactive ylide.

8 d as a weakly chelated acylamino-phosphonium ylide.

9 selenophene-type ring lowers the BDE for the ylide.

10 hosphonium salt, KH(P) rapidly generates the ylide.

11 nitrile, because of the formation of nitrile ylide.

12 t reported [3+3]-cycloaddition of a carbonyl ylide.

13 displacement of a nitro group or an iodonium ylide.

14 sfer to generate a more stable S-aryl sulfur ylide.

15 addition of the in situ generated azomethine ylide.

16 -substituted enoldiazo compounds with sulfur ylides.

17 Amines do not stabilize [3 + 2] ammonium-ylides.

18 phile-specific parameters N and sN for these ylides.

19 lecules capable of being trapped by carbonyl ylides.

20 tion of Michael acceptors with chiral sulfur ylides.

21 to all sulfur ylides but potentially to all ylides.

22 r was accessed by using preformed stabilized ylides.

23 th a transient formation of similar boronium ylides.

24 nd 1,2,4-triazoles are precursors of nitrile ylides.

25 s/Sommelet-Hauser rearrangements of ammonium ylides.

26 s involves a catalytic asymmetric azomethine ylide 1,3-dipolar cycloaddition followed by an intramole

27 ck cyclization and intramolecular azomethine ylide 1,3-dipolar cycloaddition toward the total synthes

28 esters, underwent intramolecular azomethine ylide 1,3-dipolar cycloadditions.

29 As ambident nucleophiles, ylides 1 and 2 can react at oxygen as well as at the alp

30 ophilicity parameters 4 < N < 8 for iodonium ylides 1(a-d) derived from these correlations show that

31 The iodonium ylides 1(a-d) thus have nucleophilicities similar to tho

32 of the beta-dicarbonyl-substituted iodonium ylides 1(a-d) with several pi-conjugated carbenium and i

33 hesis include an enantioselective azomethine ylide (1,3)-dipolar cycloaddition reaction to set the ab

34 n readily be intercepted by pyridine to form ylide 10b (lambdamax = 415 nm).

35 The nitrile ylides 15 are characterized by IR spectroscopy in conjun

36 /tetrazolo[1,5-a]pyrazines generates nitrile ylides 15 via pyrazinylnitrenes 13 and triazacycloheptat

37 Nitrile ylides 15a and 15b (R = H or Cl, R' = H) have allenic st

38 Nitrile ylide 15c (R = R' = CH3) has a distinctly propargylic st

39 zirene (21): one (path a) leading to nitrile ylide (17) and the major products styrene and acetonitri

40 The reaction of cinnamaldehyde with iodonium ylide 1a catalyzed by (5S)-5-benzyl-2,2,3-trimethyl-imid

41 ne-derived iminium ion 10a with the iodonium ylide 1a with the rate constant calculated by eq 1 sugge

42 methanol with a 266 nm laser produces mainly ylide 2 (lambda(max) ~ 380 nm, tau ~ 6 mus, acetonitrile

43 Ylide 2 is formed via singlet reactivity of 1, and calcu

44 show that the rate of the Wittig reaction of ylide 2 with aldehyde 14 is significantly faster than th

45 the corresponding stable C-amino phosphorus ylide 2c.

46 CH horizontal lineCH-Acc, 2) with pyridinium ylides 3, sulfonium ylide 4, and sulfonyl-substituted ch

47 as primary photoproducts and also to nitrile ylide 4 and 2,5-dimethyloxazole (5).

48 5-electrocyclization of the carbonyl nitrile ylide 4 and its structural nature (propargyl-like versus

49 Thus, the elusive carbonyl nitrile ylide 4 was captured and characterized for the first tim

50 -Acc, 2) with pyridinium ylides 3, sulfonium ylide 4, and sulfonyl-substituted chloromethyl anion 5.

51 intramolecular N-H insertion of sulfoxonium ylide 41 and conversion of ketone 32 to amine 31 in a si

52 formation of triplet vinylnitrene 4 but also ylide 5 (lambda(max) at 440 nm, tau = 13 mus).

53 Transient cyclic C-amino phosphorus ylides 6c and 6d have been prepared by intramolecular ad

54 e leads to the first example of a pyridinium ylide 8 formed from an imidazolylidene carbene, whereas

55 a maximum at 320 nm due to the formation of ylide 8, which has a lifetime on the order of several mi

56 of 1b in cryogenic argon matrixes results in ylide 8.

57 Treatment of the U(III)-ylide adduct U(CH(2)PPh(3))(NR(2))(3) (1, R = SiMe(3)) w

58 ma-lactones from the reaction of sulfoxonium ylides, aldehydes, and ketenes is described.

59 n-stabilised, semi-stabilised and stabilised ylides all occur under kinetic control by a common mecha

60 olefination using a nonstabilized phosphorus ylide and a stereoselective Heck cyclization.

61 polar cycloaddition with a simple azomethine ylide and a variety of vinyl fluorides and vinyl difluor

62 st control was conserved across a variety of ylide and amine coupling partners.

63 le the synthetic advantages of a phosphonium ylide and an iodonium salt.

64 essful trapping of the postulated azomethine ylide and azaquinone methide intermediates.

65 n between a Au carbenoid-containing carbonyl ylide and ethyl vinyl ether.

66 reaction of the in situ generated phosphorus ylide and ketenes.

67 for the formation of a hydroperoxysulfonium ylide and the ability of 1 and 2 to quench the time-reso

68 tituent, the reaction between the azomethine ylide and the alkene stops at the first step, leading to

69 ergo a subsequent decomposition onto nitrile ylide and urea.

70 tig reaction over a wide range of stabilized ylides and aldehydes.

71 ddition reaction of nonstabilized azomethine ylides and cyclic N-sulfonyl imines has been developed p

72 rmation is nonreversible with semistabilized ylides and diastereoselectivities are determined in the

73 e in reactions of triphenylphosphine-derived ylides and has previously been observed for reactions un

74 n of HNO with triarylphosphines provides aza-ylides and HNO-derived amides, which may serve as stable

75 n, whereas the difference between azomethine ylides and imines is related to lower interaction energi

76 tion reactivities of 24 mesoionic azomethine ylides and imines were investigated using density functi

77 tegy exploited the diverse reactivity of aza-ylides and imines, and featured eight different macrocyc

78 ic (3 + 2) cycloadditions between azomethine ylides and nitroalkenes, followed by catalytic hydrogena

79 se (3 + 2) cycloadditions between azomethine ylides and pi-deficient alkenes.

80 polar cycloaddition of stabilized azomethine ylides and sugar enones (dihydropyranones) derived from

81 compounds to HNO (trapped as a phosphine aza-ylide) and the corresponding barbituric acid (BA) byprod

82 yclization partners (nucleophile, azomethine ylide, and dipolarophile), and further derivatization of

83 between a novel type of ylide, i.e. nitrone ylides, and alkenes has been carried out.

84 ing: sulfoxides, sulfilimines, S,C-sulfonium ylides, and selenoxides.

85 he unequivocal identification of the nitrile ylide anti-4, which was transformed into oxazole 5.

86 three possible isomers of monomeric boronium ylides are close to true singlet ylides, with triplet st

87 These easily prepared and bench stable ylides are quickly and selectively oxidized with aqueous

88 C-Terminal peptide cyanosulfur ylides are readily converted to C-terminal peptide alpha

89 ectroscopic and computational studies of the ylides are reported.

90 [1,2]-sigmatropic rearrangements of ammonium ylides are studied by a combination of experimental, sta

91 s, provides proof of principle that iodonium ylides are suitable substrates for iminium-activated cyc

92 Although sulfur ylides are textbook reagents in organic synthesis, surpr

93 ongest superbases ever measured (phosphonium ylides) are reported, and by employing these compounds,

94 philicity and the ability to utilize the aza-ylide as a commercially available ammonia equivalent, wh

95 predicted azaquinone methides and azomethine ylides as the reactive intermediates and showed that imi

96 trated the utilization of fluorinated sulfur ylides as versatile reagents for Corey-Chaykovsky cyclop

97 initial nucleophilic attack of the iodonium ylide at the iminium ion is rate-determining.

98 An ylide-based aza-Payne rearrangement of 2,3-aziridin-1-ol

99 The new ylide-based method provides access to gamma-lactones fro

100 step (11)C-labelling process and an iodonium ylide-based radiofluorination.

101 ittig olefination of a stabilized phosphorus ylide bearing an omega-hemiacetal.

102 Stabilized ylides Bu(3)P=CH(EWG), where EWG is an ester or nitrile

103 ne intermediate apply not only to all sulfur ylides but potentially to all ylides.

104 mechanism while leaving behind the borenium ylide CB(11)(CH(3))(11), which is a strong Lewis acid an

105 tered ring structure, both having azomethine ylide character.

106 ctions of all of the three major phosphonium ylide classes (non-stabilized, semi-stabilized, and stab

107 ybrids by reaction of N-metalated azomethine ylides [Cu(II) or Ag(I)] with the appropriate chiral lig

108 idines 7a, 21a, and 21b underwent azomethine ylide cycloaddition and afforded, upon deprotection, the

109 ystems guided the pivotal [3 + 2] azomethine ylide cycloaddition cascade to form the A-C rings of the

110 0, the products of intramolecular azomethine ylide cycloadditions.

111 zed allylic amination reaction using the aza-ylide derived from 1-aminopyridinium iodide.

112 an the three-component reactions of carbonyl ylides derived from ethyl diazoacetate or alpha-aryl-alp

113 ycloaddition of sugar enones with azomethine ylides derived from natural amino acids.

114 ctions of a range of amide-stabilized sulfur ylides derived from readily available camphor-derived su

115 Photolysis of S,C-sulfonium ylides derived from thioanisol, thiophene, benzothiophen

116 hese optimized conditions, the chiral sulfur ylides (derived from camphor sulfonic acid) with differe

117 amolecular stereospecific [3 + 2]-azomethine ylide dipolar cycloaddition.

118 0]fullerene on the Re face of the azomethine ylide directed by the steroidic unit.

119 s with high ee and that stabilized sulfonium ylides (e.g., ester-stabilized) reacted with cyclic enon

120 ly been found that semi-stabilized sulfonium ylides (e.g., Ph-stabilized) reacted with cyclic and acy

121 The use of N-iminopyridium ylide enables a similar iminocyclization reaction to giv

122 The nitrile ylides exist in the matrices in the Z,Z-conformations in

123 ines are useful precursors to the azomethine ylide family of 1,3-dipoles whose cycloaddition chemistr

124 he carbonyl group with tetrahydrothiophenium ylide followed by coupling with primary amines.

125 lization of 2-azabutadiene into 7aH-indolium ylide followed by prototropic shift.

126 In acetonitrile, the formation of an ylide, followed by cyclization to the corresponding oxad

127 n energy along the series oxides, imine, and ylide for the diazonium, nitrilium, and azomethine betai

128 The utility of these chiral ylides for Wittig reactions has been briefly investigate

129 wed by a highly stereoselective Cu-catalyzed ylide formation and then a [1,2]-Stevens rearrangement.

130 tion state involving a two-point attachment: ylide formation between the alcohol oxygen and the carbe

131 t in tandem reactions, consisting of oxonium ylide formation followed by [2,3]-sigmatropic rearrangem

132 ts in a two-step process, an initial oxonium ylide formation followed by a [2,3]-sigmatropic rearrang

133 gmatropic rearrangement, as well as nitrogen ylide formation followed by azetidine ring expansion.

134 lyether coordination, intramolecular oxonium ylide formation occurs at the terminal oxygen, followed

135 opropanation and subsequent ring expansions, ylide formation with subsequent rearrangements, and C-H

136 f five distinct steps: rhodium-bound oxonium ylide formation, [2,3]-sigmatropic rearrangement, oxy-Co

137 at metal complexation facilitates azomethine ylide formation, we report that chelating aldehydes part

138 rogen insertion reactions, cyclopropanation, ylide formation, Wolff rearrangement, and cycloaddition

139 Rh(II)-catalyzed oxonium ylide formation-[2,3] sigmatropic rearrangement of alpha

140 rated acetal leads to hyperolactone C, where ylide formation-rearrangement proceeds with high selecti

141 , cyclopropanation, cyclopropenation, sulfur ylide formation/2,3-sigmatropic rearrangement, as well a

142 The tandem ylide formation/[2,3]-sigmatropic rearrangement between

143 erated from enoldiazoacetamides and carbonyl ylides formed from intramolecular carbene-carbonyl cycli

144 Azomethine ylides, formed in situ via decarboxylative condensations

145 loyment of metal carbenoid C-H insertion and ylide-forming reactions and installation of the lactone

146 first general method for generating carbonyl ylides from alpha-diazoesters that possess beta-hydrogen

147 larophiles with in situ generated azomethine ylides from l-proline or acenaphthenequinone, formation

148 catalytic formation of versatile pyridinium ylides from metal carbenes has been poorly developed; th

149 are the precursors of N-metalated azomethine ylides from which up to four new chiral centers can be g

150 precedented substrate scope for the ammonium ylide functionality, and products are generated in high

151 methyl vinyl ketone (MVK): ketone-stabilized ylide gave 25% ee, ester-stabilized ylide gave 46% ee, a

152 abilized ylide gave 25% ee, ester-stabilized ylide gave 46% ee, and amide-stabilized ylide gave 89% e

153 ized ylide gave 46% ee, and amide-stabilized ylide gave 89% ee.

154 thyl groups that makes use of a thiocarbonyl ylide generated in situ.

155 internal 2 + 3 cycloaddition with azomethine ylides generated by treatment of oxazolium salts with cy

156 +2] cycloaddition of unstabilized azomethine ylides generated from readily prepared trimethylsilyl-su

157 The addition of a stabilized sulfur ylide (generated by the rhodium-catalyzed reaction of Ph

158 ugh the Stevens rearrangement of a sulfonium ylide, generated in situ from the coupling of a copper-c

159 tive 1,3-dipolar cycloaddition of azomethine ylides, generated from bis-aziridinedicarboxylate, to C6

160 Haack cyclization, followed by an azomethine ylide generation and intramolecular cycloaddition.

161 sing NMR spectroscopy, and the efficiency of ylide generation and trapping has been evaluated via met

162 ed as the amine component for the azomethine ylide generation.

163 his process is employed in a tandem ammonium ylide generation/[2,3]-rearrangement reaction, which for

164 yde is used in the presence of an azomethine ylide, giving the corresponding highly substituted pyrro

165 oic acid group directly above the azomethine ylide group.

166 of the dimethyl triflate precursor with the ylide H2CPPh3 produced the mononuclear group 5 methylidy

167 ubstitution on the nitrile carbon of nitrile ylides has a profound effect on their structure.

168 addition reactions of N-metalated azomethine ylides has also been demonstrated by highly enantio- and

169 gioselective [2,3]-rearrangement of iodonium ylides has been developed as a general solution to catal

170 substrates using alpha-carbonyl sulfoxonium ylides has not been so far investigated, despite the pot

171 g from phenolic Mannich bases and pyridinium ylides, has been developed.

172 ion enthalpies (BDEs) of sulfur and selenium ylides have been estimated by applying MP2/6-311++G(3df,

173 In particular, vinylsulfonium ylides have been neglected so far.

174 N-H sulfilimines and CH2-S,C-sulfonium ylides have low BDEs, unless the sulfilimine or S,C-sulf

175 carried out with deuterium-labeled sulfonium ylides, higher ee's were observed in all cases since pro

176 tudy of the reaction between a novel type of ylide, i.e. nitrone ylides, and alkenes has been carried

177 thoxycarbene from the dibenzothiophene-based ylide in neat thiophene, it is shown that the thienylmal

178 dimethyl-1,3-cyclohexanedione phenyliodonium ylide in the presence of alkyl halides yields the corres

179 3-pyrrolyl BODIPY with different alkyl/aryl ylides in CH2Cl2 at room temperature for 2 h followed by

180 rearrangement of nitrile-stabilized ammonium ylides in conjunction with the reductive removal of the

181 reaction of vinyl benzoxazinones and sulfur ylides in good yields and good enantioselectivities.

182 a product of rearrangement of the thiophene ylide, in contrast to thermolysis results.

183 The examined ylides include the following: sulfoxides, sulfilimines,

184 For the thiophene-based ylide, insertion of the carbene into the alpha-CH bond o

185 rboxyl donor and the involvement of a unique ylide intermediate as the carboxyl acceptor in the CmoA-

186 s to conditions under which the long-elusive ylide intermediate could be stabilized.

187 The key sulfur ylide intermediate for the rearrangement was formed by t

188 sult of the stereogenic sulfur center in the ylide intermediate, two diastereomeric transition states

189 -H insertions as well as reactions involving ylide intermediates with similar selectivity profiles to

190 f C-H activation, migratory insertion of the ylide into the carbon-metal bond, and protodemetalation,

191 The formation of the [3 + 2] phosphorus-ylide is exergonic, and hence, the [3 + 2] cycloaddition

192 DEs, unless the sulfilimine or S,C-sulfonium ylide is stabilized by an electronegative substituent on

193 arrangement of a nitrile-stabilized ammonium ylide is the key step of a very short and practical synt

194 -substituents in the case of semi-stabilized ylides is confirmed and is accommodated by the cycloaddi

195 tive [2,3]-rearrangement of allylic ammonium ylides is described.

196 A cascade sequence involving azomethine ylide isomerization followed by Mannich cyclization form

197 the greatest extent with the most stabilized ylide (ketone).

198 e reacts with acetonitrile to form a nitrile ylide (lambdamax = 370 nm), and with cyclohexane by C-H

199 a diazo ketone, with an ether to produce an ylide-like intermediate that rearranges to produce E- or

200 The reactivity of ylide-like phosphasilene 1 [LSi(TMS) horizontal lineP(TM

201 e limited in phenyl anions, and as a result, ylide-like, rather than carbene-like, resonance structur

202 benzyl ether derivative to asymmetric sulfur ylide-mediated epoxidation with up to 92% ee (14 example

203 p to 200 cm(-1) in the IR absorptions of the ylide moieties.

204 -dienoate as a dipolarophile with azomethine ylides, nitrones, and nitrile oxides in good yields.

205 Thermal decomposition of the phenyliodonium ylide of lawsone gives rise to a highly reactive cyclic

206 de-mediated reaction between cyclic iodonium ylides of 1,3-dicarbonyls and 3-alkylidene-2-oxindoles r

207 initial electrophilic attack of the iodonium ylide on the C(beta) position of the diphenylketene, fol

208 reaction of an in situ generated azomethine ylide onto a cyclopropene.

209 med by addition of a COOEt-stabilized sulfur ylide onto the Michael acceptor.

210 lar cycloadditions of N-metalated azomethine ylides onto C60 yielding a full stereodivergent synthesi

211 s a base for the formation of the azomethine ylide or 1,3-dipole.

212 f either 1,3-cyclohexanedione phenyliodonium ylide or 5,5-dimethyl-1,3-cyclohexanedione phenyliodoniu

213 enhancement have included covalent addition, ylide or carbene formation, and most recently concerted

214 as a four-atom component, and Corey's sulfur ylide or ethyl bromoacetate acts as a one-atom carbon so

215 ion or decarboxylation to give an azomethine ylide or nitrone followed by intramolecular dipolar cycl

216 al 1,3-dipolar cycloaddition between nitrile ylides or nitrilium triflates and imines.

217 s (LFP) experiments, CCl2 forms chromophoric ylides or oxides with pyridine, 2-picoline, thioanisole,

218 hanism of the reactions of formyl-stabilized ylide Ph3P horizontal lineCHCHO (1) and acetyl-stabilize

219 rizontal lineCHCHO (1) and acetyl-stabilized ylide Ph3P horizontal lineCHCOMe (2) with benzhydrylium

220 roxyacetal which was added to the phosphorus ylide Ph3PCCO.

221 ttig olefination reaction with the cumulated ylide Ph3PCCO.

222 The nitrile ylide PhC(-) horizontal lineN(+) horizontal lineC(CH3)2

223 The nitrile ylide PhC(-) horizontal lineN(+) horizontal lineCH2 (30)

224 e 1,3-dipolar cycloaddition of an azomethine ylide (Prato reaction) with M(3)N@I(h)-C(80) (denoted as

225 f (18)F-FPEB was achieved by reaction of the ylide precursor (4 mg) with (18)F-Et4NF in dimethylforma

226 With the iodonium ylide precursor, (18)F-LY2459989 was prepared at high ra

227 The choice of nucleophile, azomethine ylide precursor, and dipolarophile was crucial to the su

228 method that uses a hypervalent iodonium(III) ylide precursor, to prepare the radiopharmaceutical (18)

229 use of a new trifluoromethylated azomethine ylide precursor, which leads to a series of fluorinated

230 sulfoxide were determined using the pyridine ylide probe method.

231 The reactions of alkyl-substituted carbonyl ylides proceed with high regioselectivity and diastereos

232 Radiofluorination of iodonium (III) ylides proved to be an efficient radiosynthetic strategy

233 The resulting parent ylides provide convenient access to a structurally diver

234 erivatives of dimethylmalonate thiophene-S,C-ylide provides dicarbomethoxycarbene, which can react wi

235 A cyclic beta-dicarbonyl phenyliodonium ylide reacted with various substituted styrenes under Rh

236 able to rationalize the outcome of different ylide reactions bearing a variety of substituents in ter

237 stable toward hydrolysis and aza-phosphonium ylide reactions.

238 An oxonium ylide rearrangement formed the trisubstituted tetrahydro

239 d stereospecifically into a variety of onium ylide rearrangement products, as well as compounds that

240 Despite the importance of allylic ylide rearrangements for the synthesis of complex molecu

241 ped as a general solution to catalytic onium ylide rearrangements.

242 s that are not accessible by classical onium ylide rearrangements.

243 rect formation of the corresponding carbonyl ylide resulted from the electrophilic addition of diamin

244 the azirinium ylide to metal-free azirinium ylide, ring-opening of the latter to give a 1,5-diazahex

245 the formation of a methyl triflate-based pre-ylide salt that upon treatment with base in the presence

246 Furthermore, a clear correlation of ee with ylide stability was observed in reactions with methyl vi

247 rimental findings reveal that the azomethine ylide stabilized by an allylic group cycloadds to [60]fu

248 stigation demonstrates the importance of the ylide-stabilizing group for obtaining the desired nucleo

249 red, and the possibly quite general role of "ylide" structures in Lewis acid induced substitution rea

250 This species, or its corresponding sulfur ylide, subsequently adds into the substrate, initiating

251 to substitutions on both the alkylidene and ylide substrates and provided access to 19 new, densely

252 diofluorination via the spirocyclic iodonium ylide technology.

253 presumably generates a transient azomethine ylide that undergoes cycloaddition with dipolarophiles i

254 [2,3]- and [1,2]-rearrangements of iodonium ylides that are controlled by copper catalysts bearing d

255 The alkyl-substituted carbonyl ylides that are generated in this fashion are highly rea

256 and convenient entry to reactive azomethine ylides that can (1) be protonated and reduced with high

257 esilylation provides endocyclic unstabilized ylides that successfully undergo cycloaddition with a ra

258 esilylation generates exocyclic unstabilized ylides that undergo cycloaddition with unsymmetrical alk

259 desilylated to give endocyclic unstabilized ylides that undergo intermolecular cycloadditions with c

260 nt Michael-addition approaches of the sulfur ylide, the transition state (TS) energies for the format

261 The resulting ylide then rearranges, using an internal carbonyl base,

262 of the metal-bound complex of the azirinium ylide to metal-free azirinium ylide, ring-opening of the

263 Utilizing the cycloaddition of an azomethine ylide to pentafluorosulfanylalkynes, a series of dihydro

264 Thus, following addition of a stabilized ylide to the Michael acceptor, rapid and reversible intr

265 e intermediate, Michael-type addition of the ylide to the o-quinone methide, followed by intramolecul

266 e to the rhodium carbenoid from the iodonium ylide to yield a halonium intermediate that undergoes ha

267 ile at the nucleophilic carbon center of the ylides to give iodonium ions, which rapidly expel iodobe

268 The development of a direct ylide transfer to carbonyl derivatives and of a sulfoxid

269 ted to the same conditions, both addition of ylide trapping reagents and net isomerization of cis to

270 The reaction appears to proceed through an ylide-type mechanism, where the unique strain and struct

271 an effect that is common to reactions of all ylide types strongly argues for the operation of a commo

272 treating formylated BODIPYs with alkyl/aryl ylides under simple room temperature conditions.

273 dienylidenetriphenylphosphorane (the Ramirez ylide), unexpectedly and contrary to a number of earlier

274 tructurally diverse set of chiral stabilized ylides via functionalization.

275 h in situ generated nonstabilized azomethine ylides via the domino Mannich reaction-dipolar cycloaddi

276 g reaction of anisaldehyde with a stabilized ylide was studied by a combination of (13)C kinetic isot

277 The resulting ester ylide was treated with hydrochloric acid to liberate the

278 The Wittig reaction with nonstabilized ylides was performed under salt free conditions in most

279 By applying this model to S-, N-, and P-ylides we have been able to rationalize the outcome of d

280 d (in phosphonium part) phosphonium-iodonium ylides were synthesized.

281 a hydrogen acceptor, such as the phosphorus ylide, when combined with the alkylidene complex (PNP)Ti

282 dium hydroxide regenerated the corresponding ylide, which underwent a spontaneous intramolecular Witt

283 sters to generate metal-coordinated iodonium ylides, which undergo [2,3]-rearrangements with high sel

284 These conjugated ylides--which represent a subclass of mesomeric betaines

285 tions (1,3-DCs) of isatin-derived azomethine ylide with allenes have been established, which efficien

286 pyridinium, isoquinolinium, and quinolinium ylides with acceptor substituted dipolarophiles (arylide

287 reaction of these mixed phosphonium-iodonium ylides with acetylenes opens a way to new furyl annelate

288 sed on the reactions of stabilized sulfonium ylides with acyclic enones which unexpectedly gave low e

289 Treatment of beta-dicarbonyl iodonium ylides with acyl chlorides yields alpha-chloroenones wit

290 ion reaction of in situ generated azomethine ylides with an excess of C60.

291 nstants k2 for the reactions of the iodonium ylides with benzhydrylium ions correlate linearly with t

292 the cross-coupling reactions of sulfoxonium ylides with C(sp(2) )-H bonds of arenes and heteroarenes

293 pyridinium, isoquinolinium, and quinolinium ylides with diarylcarbenium ions, quinone methides, and

294 e reaction of beta-dicarbonyl phenyliodonium ylides with diphenylketene at room temperature affords m

295 New reactions of azomethine ylides with nontraditional dipolarophiles are reported.

296 The reactions of aryl-stabilized sulfur ylides with organoboranes has been studied under a varie

297 semistabilized, and nonstabilized phosphorus ylides with various carbonyl compounds in the presence o

298 O quantitatively (trapped as a phosphine aza-ylide) with half-lives spanning 3 orders of magnitude (m

299 ic boronium ylides are close to true singlet ylides, with triplet states approximately 50 kcal/mol hi

300 nt nucleophilic attack of the epoxide by the ylide yields a bis-anion, which upon a 5-exo-tet ring-cl