Phosphonio-substituierte 1,3-Diphosphanaph thaline aus der a,o-Kondensation von Phosphonium-benzyliden / Phosphonio-Substituted 1,3-Diphosphanaphthalenes from the α.o-Condensation of Phosphonium-benzylides
3-dibromo-substituted title compounds 5b, c result from the condensation of triphenylphosphonium-bis(trimethylsily1)methylide 1 with PC13 and PBr3. The chloro derivative 5b undergoes a variety of single and double substitution reactions, of which some have merely been tested and others have been made preparative use of. The substitution of one chloride by an ylidyl, amino, phosphino, or metal carbonyl group is accompanied
From the reaction of trimethylsilylylides with AsCl3 the dichloroarsanyl ylides 2b and 5b are obtained. As shown by X-ray structure determination, their AsCl2 groups deviate systematically from the symmetric orientation. This conformation enables an effective charge transfer from the ylide moiety to one of the As-Cl bonds, which as a consequence is up to 15 pm longer than the other. At the same time
Die Kondensation von Ylidylchlorphosphanen mit Phosphanen und Bis(diphenylphosphanyl)methan und -amin / The Condensation of Ylidyl Chlorophosphines with Phosphines and Bis(diphenylphosphino)methane and -amine
12. The chloromethyl diphosphinimine 13c enters a cyclization to give the 1,2,3,5-azatriphosphole derivative 14, the structure of which has been solved by X-ray analysis. From the reaction of ylidyl bis(chlorophosphanes) 17 and 20 with the same reagents the 1,2,4,5-tetraphosphinine derivative 18 and the 1,2,3,5,6-azatetraphosphinine derivatives 19 and 21 are obtained.
Phosphonio-substituierte Tetrahydro-1,3-diphosphinine und Tetrahydro-1,2,6-azadiphospliinine / Phosphonio-Substituted Tetrahydro-1,3-diphosphinines and Tetrahydro-1,2,6-azaphosphinines
bis(dichlorophosphanyl)methylene triphenylphosphorane 2 or the bis(dichlorophosphanyl)aniline 3 to form cationic six-membered rings: A tetrahydro-1,3-diphosphinine (4) with three phosphonio or phosphoranediyl substituents in 2,4,6-position and a tetrahydro-1,2,6-azadiphosphinine (5) carrying two such substituents in 3,5-position. The bromide of the latter was used for an X-ray structure analysis. The PIII ring
Tetrachloro- and tetrabromodiphosphanyitriphenylphosphonium ylides give an equilibrium mixture of all possible halogen-exchange products. Their strongly varying coupling constants J(Ph(3)P-C-P) are explained as resulting from varying shares of two conformations. The chemical shifts delta(31)P of the phosphanyl groups seem to reflect their competition for the electron transfer from the ylide carbon atom. Related examples are included for comparison.