| Abstract: | (tBu)2P]2P? PP(tBu)2]2 from LiPP(tBu)2]2 and 1,2-Dibromomethane. Pyrolysis of tBu2P? P?P(Br)tBu2 All products of the reaction of tBu2P]2PLi 1 with 1,2-dibromoethane 2 were investigated. Already at ?70°C tBu2P? P?P(Br)tBu2 3 as main product and tBu2P]2PBr 4 are formed. Only with an excess of 1 also tBu2P]P? PP(tBu)2]2 5 is obtained. Warming of a pure solution of 3 in toluene from ?70°C to ?30°C leads to 4 , and at 20°C tBu2PBr and the cyclophosphanes P4P(tBu)2]4 and P3P(tBu)2]3 are observed. 5 does not result from 3 , it's rather a byproduct from the reaction of 1 with 4 . Also the ylide 3 and 1 yields 5 . |
