The reaction of the carbanion of di-Et allylphosphonate (I) with BzH and p-methylbenzaldehyde was reported. A series of solvents with different polarity was employed to study the effect of solvents on the regioselectivity of the reaction. The reaction was kinetically controlled. The reaction took place predominately on the a-position in THF, and more g-substituted product was obtained than the a-substituted product in n-pentane. With the addition of complexing agent, such as TMEDA or HMPT, the effect of solvents on the regioselectivity of the reaction decreased.

Key words: ORGANO PHOSPHORUS COMPOUNDS, PHOSPHONIC ACID ESTER, SELECTIVITY, ETHYL ESTER, PROTON MAGNETIC RESONANCE SPECTROMETRY, SOLVENT EFFECT, BENZALDEHYDE, ALLYL GROUP, CARBANION