The Wittig Reaction

Abstract

In 1953 Wittig and Geissler found that reaction of benzophenone with methylenetriphenylphosphorane gave 1,1‐diphenylethylene and triphenylphosphine oxide in almost quantitative yield; the phosphine had been prepared from triphenylmethylphosphonium bromide and phenyl lithium. The discovery led to the development of a new method for the synthesis of olefins, under the name Wittig reaction. One advantage of this new method is that the carbonyl group is replaced specifically by a carbon‐carbon double bond without the formation of isomeric olefins. In contrast, the older method of converting carbonyl compounds to olefins using the Grignard reaction usually give a mixture of isomeric olefins. Another advantage is the Wittig reaction is carried out under mild conditions. Discussions of modern techniques for the preparation of methylene phosphoranes are included in this review.

New series of monoamidoxime derivatives displaying versatile antiparasitic activity

“…The reaction of cyano derivatives synthesized from both cyclization mediated by manganese(III) acetate and Suzuki-Miyaura cross-coupling reactions (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31), with hydroxylamine hydrochloride and potassium tert-butoxide in DMSO [30] led to conversion of the cyano group into amidoximes 32-51 in moderate to excellent yields (28-100%) as reported in Table 4. almost halves the reaction yield.…”

The McMurry Coupling and Related Reactions

“…294 One of its advantages is that the configuration of the olefination products can be controlled by careful selection of the phosphorus reagent and reaction conditions, especially in the case of the preparation of 1,2-disubstituted ethenes. The Horner-Wadsworth-Emmons reaction using α-carbanions of phosphonates (Scheme 23) 295 and the Horner-Wittig reaction using phosphine oxide anions are also powerful methods for carbonyl olefination.…”

Tetramethyl 1,1,2-triphenyl-2H-1λ5-phosphole-2,3,4,5-tetracarboxylate

“…For general background to derivatives of dimethylenesuccinic anhydride (fulgides), see: Hadjoudis & Mavridis (2004); Gordaliza et al (1996); Datta et al (2001); Stobbe (1893); Maercker (1965); Shaw et al (1967). For a detailed study of adduct formation from triarylphosphines and acetylenedicarboxylate, see: Waite et al (1971).…”

“…a need for the use of strong bases, which may cause resinification of some aldehydes, there have been continuous efforts towards development of alternative approaches. Especially the Wittig reaction (Maercker, 1965) between dialkyl bis[triphenylphosphoranylidene]succinates and the appropriate benzaldehydes appeared to be of particular value. The ylide component of the Wittig reaction seemed to be easily accessible by the condensation between triphenylphosphine and dialkyl acetylenedicarboxylate.…”