The Wittig reaction is one of the most important and versatile reactions in organic chemistry for synthesizing alkenes with unambiguous positioning of the double bond. Since its discovery in the early 1950s 1, 2, the Wittig reaction has been studied very extensively from both theoretical and synthetic aspects 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 and highly recognized for its simplicity, efficiency, and generality. The prototype Wittig reaction involves the reaction of a phosphonium ylide with an aldehyde or a ketone as depicted in reaction (R1).The stereoselectivity benzyltriphenylphosphonium chloride is highly dependent on the substituents bonded to the ylidic carbon and to the phosphorus atom, and on the exact reaction conditions. According to their general reactivity, three categories of phosphonium ylides, namely nonstabilized, semistabilized, and stabilized ylides, have been classified. The Wittig reaction has been shown to yield preferentially E alkenes for stabilized ylides having strongly conjugating substituents (e.g., COOMe or CN); mixtures of the Z and E alkenes for semistabilized ylides bearing mildly conjugating substituents (e.g., phenyl, vinyl or allyl); and mainly contrathermodynamic Z alkenes for nonstabilized ylides lack such conjugating functionalities (e.g., alkyl). Most of the studies of the Wittig reactions were carried out homogeneously in organic solvents (e.g., THF, C₆H₆, CCl₄, CHCl₃, DMF, and MeOH).