Phosphorverbindungen ungewöhnlicher Koordination, 31 [1] Cycloaddition von Diazoverbindungen an ein P—Chlor-phosphaalken / Phosphorus Compounds with Unusual Coordination, 31 [1] Cycloaddition of Diazo Compounds onto a P—Chloro-phosphaalkene

Abstract

Chloro bis(trimethylsilyl)methylene phosphane (4) reacts with the diazo compounds 5, 10, 15 and 20 even at low temperatures with formation of the 3H-1,2,4-diazaphospholes 6,11,16 and 21. The products are unstable and decompose either with elimination of nitrogen to yield 1-chloro phosphiranes (9,14, 19 and 22), or isomerize with aromatization (11 → 13) or transformation into 4,5-dihydro-1,2,4-diazaphospholes (6 → 8, 16 → 18) by trimethylsilyl shifts. Silyl groups attached to ring nitrogen are easily hydrolized (8 → 7,13 → 12, 18 → 17), those attached to ring carbon are cleaved by treatment with potassium fluoride in dimethyl formamide (7 → 23, 12 → 24).