Reactions of Nitrosovinylphosphonates with Electron-Rich Alkenes and Heterocycles

Abstract

In the presence of a base, chlorohydroxyiminophosphonates are converted in situ into the corresponding transient nitrosovinylphosphonates, which react as heterodienes with electron-rich alkenes and heterocycles producing oxazines and open-chain oximes in moderate yields and good selectivity. This approach may be regarded as a new strategy for the synthesis of precursors of α-amino phosphonic acids.

Keywords:

• α-aminophosphonates
• chloro-hydroxyiminophosphonates
• Diels-Alder reactions
• nitrosoalkenes
• nitrosovinylphosphonates

Acknowledgments

Thanks are due to Dr. T. L. Gilchrist for helpful discussions and Fundação Ciência e Tecnologia, UID 272/94, for financial support.