Nature of the Ylide and Carbonyl Compound

The nature of the reactant carbonyl group in the substrate also influences the stereoseledivity of the Wittig readions for example, primary aliphatic aldehydes 

Triphenylphosphorane ylides are readily accessible by the reaction of triphenylphosphine with a suitable halide (See Section 1.2.3) 

Factors thatfivor the E-alkene Factors that dirfavor the E-alkene 

Aprotic conditions A catalyic amount of benzoic addl Li and Mg salts in DMF as solvent Use of a-oxygenated aldehydes or methanol as solvent 

Factors thatfavor the Z-alkene Factors that di avor the Z-alkene 

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