An efficient and practical protocol for completely regioselective and highly stereoselective synthesis of vinyldiazaphosphonates from N-heterocyclic phosphine (NHP) and allenes via phospha-Michael/intramolecular nucleophilic substitution reaction has been developed. This transformation enabled the synthesis of valuable densely functionalized vinyldiazaphosphonates with a β-, γ-unsaturated ester moiety under mild reaction conditions. Synthetic utility of vinyldiazaphosphonates was demonstrated by a series of synthetic manipulations.

Utility of Bifunctional N-Heterocyclic Phosphine (NHP)-Thioureas for Metal-Free Carbon-Phosphorus Bond Construction Toward Regio-and StereoselectiveFormation of Vinylphosphonates. -This novel N-heterocyclic phosphine--promoted phospha-Michael/intramolecular nucleophilic substitution reaction allows for the stereoselective construction of vinyldiazaphosphonates in moderate to excellent yields. The Michael addition of the NHP to -substituted or -substituted allenes proceeds with complete regioselectivity and reveals good tolerance of various electron--withdrawing groups on the allenes. This protocol represents the first general application of bifunctional NHPs in organic synthesis to facilitate the rapid C-P bond forming approach to vinylphosphonate compounds and is a complement to classical methods like metal-promoted synthesis of vinylphosphonates. -(MULLA, K.; ALESHIRE, K. L.; FORSTER, P. M.; KANG*, J. Y.; J. Org. Chem. 81 (2016) 1, 77-88, http://dx.doi.org/10.1021/acs.joc.5b02184 ; Dep. Chem. Biochem., Univ. Nev., Las Vegas, NV 89154, USA; Eng.) -H. Hoennerscheid