PHOSPHANE ALKYLENES .55. REACTIONS OF ALK YLIDENETRIPHENYLPHOSPHORANES WITH NITRATING REAGENTS

The reaction of phosphonium ylides 1 with N2O4 (2) is strongly influen ced by the natur of the substituents of the starting ylide. Formation of alpha-nitro-alpha-nitrosoalkanoates 8, nitrolic acid 11, and nitril es 13 was realized. Nitration at the phenyl group of benzylidenephosph oranes 24 or at the gamma-position of allylidenephosphoranes 30 accomp anied by transylidation and oxidation processes leads to the formation of nitro-substituted ylides 26 and 32, respectively. Strongly basic y lides and ethyl nitrate (34) undergo complex reactions as is shown in the formation of the aziridinyl-substituted ylide 40 from ethylidenetr iphenylphosphorane (9) and 34. Allylidenetriphenylphosphoranes 41 are nitrated by ethyl nitrate (34) at the gamma-position affording (gamma- nitroallylidene)triphenylphosphoranes 43, from which nitro dienes 45 a re available. In the reaction of 1-(dimethylamino)-2-nitroethylene (46 ) with phosphonium ylides nitro-vinylation of the starting ylide takes place.