Wittig reactions are most commonly used to convert aldehydes and ketones to alkenes. [1][2][3] Most often, the Wittig reaction is used to introduce a methylene group using methylenetriphenylphosphorane (Ph 3 P=CH 2). Using this reagent, even a sterically hindered ketone such as camphor can be converted to its methylene derivative.

2021年4月10日 · Geissler研究了五价磷的化学性质，描述了甲基三苯磷 ( Ph3P=CH2 )与二苯甲酮的反应，定量 生成 1,1-二苯 乙烯 和三苯氧 膦 ( Ph 3 P= O)。 Wittig认识到这一发现的重要性，并进行了系统的研究，将几种磷酸与不同的醛和酮反应得到相应的烯烃。

Wittig反应（维蒂希反应）是醛或酮与 磷叶立德 （Wittig试剂）发生亲核加成生成烯烃反应，该反应由德国化学家 Georg Wittig 在1954年发现，为此他获得了1979年的 诺贝尔化学奖。 Wittig反应在烯烃合成上有着广泛的应用，可用于合成双键位置确定的烯烃。 Wittig反应的反应物一般是醛/酮和单取代的磷鎓内盐。 使用活泼叶立德时所得产物一般都是Z型的，或Z/E异构体比例相当；而使用比较稳定的叶立德时，或在 Schlosser改进 的条件下，产物则以E型为主。 Wittig反应的第一 …

2023年1月23日 · Organophosphorus ylides react with aldehydes or ketones to give substituted alkenes in a transformation called the Wittig reaction. This reaction is named for George Wittig who was awarded the Nobel prize for this work in 1979.

2018年2月6日 · Below is a useful reaction called the Wittig reaction that achieves this transformation. It won its inventor, Georg Wittig, the 1979 Nobel Prize in Chemistry (along with the father of hydroboration, H.C. Brown). The two components of this reaction are:

Methylenetriphenylphosphorane is an organophosphorus compound with the formula Ph 3 PCH 2. It is the parent member of the phosphorus ylides, popularly known as Wittig reagents. It is a highly polar, highly basic species.

Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P (C 6 H 5) 3 and often abbreviated to P Ph 3 or Ph 3 P.

最简单的维蒂希试剂是亚甲基三苯基膦（Ph3P+−C−H2），是一个橙黄色固体，对空气和水都不稳定，可通过三苯基膦和溴甲烷生成的溴化三苯基甲基鏻 Ph3P+-CH3·Br−在干燥乙醚和氮气流下用苯基锂处理失溴化氢制得：[14]

2025年2月24日 · A common Wittig reagent is methylenetriphenylphosphorane (Ph 3 P=CH 2) which is synthesized by reacting Triphenyl phosphine with methylbromide followed by deprotonation with n -butyllithium. Because an S N 2 reaction is used in the synthesis of ylides, methyl and primary halides perform the best.

【结构式】 Ph3P=CH2 【物理性质】 白色晶体，mp 96 oC。溶于醚、 THF、DME、苯、甲苯、DMSO。水或者质子溶剂会将该试剂彻底破坏。 【制备和商品】 该试剂无法作为商品购得，必须在使用前制备该试剂的溶液。