Relative Ease of Formation of Alkylidine(oxo and thioxo)phosphorane Intermediates in Nucleophilic Substitution at Phosphonyl and Thiophosphonyl Centres
Abstract
The conversion of R2CHP(X)(NEt2)Cl (R2CH=9-fluorenyl) into R2CHP(X)(NEt2)2via the intermediate R2CP(X)NEt2 (elimination–addition mechanism) is much faster when X=S than when X=O.