Cyclic organophosphorus compounds. XVIII—the mass spectroscopy of some 2-amino-1,3,2-dioxaphosphorinans,cyclic phosphorodiamidates and phosphorodiamidothionates

Stepwise replacement of O in 1,3-dioxa-2-phospha(V)-cyclohexanes (or related ring systems) by NR (R=H or Me) leads to an increase in the stability of the hetero-ring ions produced under electron impact conditions. In the case of the 2-phenoxy derivatives, there is also an increased abundance of [M? PhO]⁺ or [M? PhOH]⁺ ions, and, for the 2-sulphides, a reduction in the abundance of [M-S]^+˙ and [M-SH]⁺ ions, with a concurrent increase in that of [M-PhS]⁺ ions. Such trends have been correlated with ultraviolet photoelectron spectral data on a qualitative basis.