GRAPHICAL ABSTRACT
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ABSTRACT
Racemic and optically active (+)-(S)-(diphenoxyphosphoryl)methyl p-tolyl sulfoxide were prepared and used as Horner olefination reagents. Their reaction with aromatic and aliphatic aldehydes afforded the corresponding racemic and enantiomeric α,β-unsaturated sulfoxides with moderate to high Z-selectivity. The E/Z ratio was found to be dependent on the structure of aldehyde, nature of base, reaction conditions, and addition of 18-crown-6.