Mohamed Lazraq

SYNTHESIS OF TWO STABLE DIPHOSPHENES WITH A NEW STABILIZING SUBSTITUENT

Abstract Two new diphosphenes 7 and 10 have been synthesized by action of DBU on trichlorogermylphosphines 4 and 8; this route involves the intermediate formation of chlorophosphines 5 and 9. Diphosphenes 7 and 10 are stabilized by the 2,6-bis(trifuoromethyl)phenyl group which presents both steric and electronic effects and is used for the first time in phosphorus chemistry.

From a germene to a transient germirane

Abstract Reaction of dimesityl(fluorenylidene)germene, 1, with diazomethane leads, depending on the experimental conditions, to the germapyrazoline 3 or 4. Thermal decomposition of 4 gives an unstable germirane 14, which was identified from its [3] → [2 + 1] decomposition products, viz. 9-methylenefluorene 12 and dimesitylgermylene 15.

Unusual formation of a tricyclic compound from a phosphaalkyne and an arylgermene exhibiting 1,3-diene characteristics

The phosphaalkyne 2 reacted with the germene 1 in a molar ratio of 2:1 with formation of the germadiphosphatricyclooctene 5; this is rationalised in terms of a Diels–Alder reaction of the substrates followed by an ene reaction and intramolecular cycloaddition.

New Stable Diphosphenes

Abstract Since the isolation of the first stable diphosphene by YOSHIFUJI, some other diphosphenes have been prepared and stabilized by very bulky substituents. We have recently described the synthesis, via a germylated way, of the bis [bis (trimethylsilyl)methyl]diphosphene 1, one of the least crowded stable diphosphenes: