Cyclic organophosphorus compounds—II

The IR spectra of 47 1,3,2-dioxaphosphorinanes, mostly new compounds, have been recorded and discussed. Assignments have been made to PO, POC (alkyl and aryl), PS and PN stretching motions. In addition,it is suggested tentatively that multiple bands found at around 1000 to 1050 cm−1 and at around 1150 to 1200 cm−1 may be due to ring PO(C) vibrations.