A three-component reaction involving isocyanide, phosphine and ketenimine functionalities

Abstract

A three-component reaction involving diphosphinoketenimines, isocyanides and water or ethanol leading to the formation of new five-membered azaphosphaheterocycles is described.

Isocyanide-based multicomponent reactions in the synthesis of heterocycles

“…Ruiz et al disclosed synthesis of azaphosphaheterocycles 732 through one-pot multi-component reaction of isocyanides 729, diphosphinoketenimines 730 and water or ethanol 731 (Scheme 193). 280 The authors proposed a mechanism based on formation of adduct 733 via a-addition of 730 to isocyanide 729. Subsequently, adduct 733 tolerated oxidative addition at the exocyclic diphenylphosphino group to afford 734.…”

The thriving chemistry of ketenimines

“…13a,b,d In these cases, oxidative addition of Pd(0) to N-sulfonyl-N-allyl-ynamides 39 leads to the generation of ynamido-Pdp-allyl complexes 44. The complexes can be trapped with primary and secondary amines as well as enamines to furnish the corresponding amidines which are allyl transferred (45), deallylated (46), and vinylogous (47), respectively. When excess Scheme 8 Preparation of ketenimines with heteroatoms (S, Br, Si) on C-terminus.…”

“…cycloadditions of ketenimines with isonitriles were reported by Ruiz and co-workers in 2011. 47 With the participation of a phosphorous atom, the treatment of diphosphinoketenimines 142 with a mixture of isonitrile and water results in azaphospholene derivatives 143 (Scheme 44). The first step of this cascade process is a [3+1] cycloaddition.…”

Four-membered rings from isocyanides: Developments since the mid 1980s

“…29,31,32 Best suited are nitrile imines bearing a donor-substituted phenyl group at the terminal nitrogen like 34, they gave cycloadducts 36 with a wide variety of isocyanides (Scheme 8). 31,32 These four-membered rings, however, eluded isolation, but their formation could be inferred from products formed by [2+2] cycloreversion into benzonitrile and a carbodiimide (37), by ring expansion to a quinoxaline (38), and finally by [2+2] cycloreversion of the secondary adduct 39 into 37 and a 1,2,4-triazole (40). Besides these compounds products such as 41-45 were found; formally, they derive from the linear adduct 35 which in the case R = t-Bu could be detected spectroscopically.…”