| Abstract
| - Soluble poly(ethylene glycol) (PEG)-supported telluride 2 was designed and synthesized for catalyticWittig-type reactions. It was found that the catalytic loading could be reduced from 20 to 2 mol %by the introduction of PEG (even to 0.5 mol % when some telluride salts were used as the catalyst).Under the catalytic reaction conditions, a wide variety of aldehydes with different structures couldreact with bromoacetate to afford β-substitutited or α,β-disubstituted unsaturated esters in highyields with excellent E-stereoselectivity. The modified process, by using sodium bisulfite insteadof triphenyl phosphite, represented a very simple product isolation procedure. The roles of PEGfor promoting the ylide formation and stabilizing the catalytic species were disclosed. The mechanismwas also studied.
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