PHOSPHORSUBSTITUIERTE N,N′ -DIMETHYLTHIOHARNSTOFFVERBINDUNGEN. IV. N,N′-DIMETHYLDIAZAPHOSPHETIDINTHIONE

Abstract

In the reaction of N,N′-dimethyl thiourea, 1 with n-butyl lithium, followed by some dichlorophosphorus(III) compounds, in the presence of triethylamine the phosphadiazetidine thiones, 2-5 were obtained. In contrast to the analogous urea derivatives dynamic behavior was observed in the room temperature ¹H and ¹³C n.m.r. spectra of 2-5.

Oxidation reactions at the λ³P atom of 2 are described, involving as oxidizing agents bis(trimethylsilyl)peroxide (→6), elemental sulfur (→7), tetrachloro-o-benzoquinone (TOB) (→9), and phenyl azide (→10).

An unusual reaction with hexafluoroacetone (HFA) was observed for the dimethylamino-substituted diazadiphosphetidine thione, 2: two molecules of HFA were oxidatively added to the λ³P atom, producing a perfluoropinacolyl ring system, while a further molecule of HFA was inserted into a PN bond of the diazadiphosphetidine thione ring system.

Key Words:

• N,N′-dimethyl thiourea
• diazadiphosphetidine thiones
• P‒N-rotation
• hexafluoroacetone insertion.