An efficient synthesis of oxiranyl oxazolines and elaboration to acyl oxiranes

Article abstract of DOI:10.1016/S0040-4039(98)01096-X

Deprotonation of oxazolinyl oxirane 1a with sec-BuLi/TMEDA at -100 °C in Et₂0 furnished oxazolinyl oxiranyllithium 1b, which could be trapped with electrophiles to give oxiranes 1c-g. The reaction of 1b with aldehydes produced diastereomers syn (2a-d) and anti (3a-d). Oxiranyllithium 1i from trans-1-oxazolinyl-2-p-tolyl epoxy ethane 1h was found to be configurationally stable while oxiranyllithium 1I, generated from the cis isomer 1k, was not. Oxazolinyl epoxides 1d, 1j and 1m could be deblocked to acyl oxiranes 5a-e through oxazolidines 4a-e.