First 1‐phospha‐1,3‐dienes unsubstituted in the carbon chain by pyrolysis of diallylphosphines: A novel route to the phosphorus—carbon double bond

Abstract

Allylic phosphine systems were studied as phosphorus-carbon double bond precursors. I -Phenyl and Ibutyl-1 -phospha-l,3-dienes were generated by pyrolysis at 350-460°C of the corresponding diallyl phosphines in a stirred-flow reactor. The unsubstituted phosphadienes generated in this manner dimerized; the formation o f [ 4 + 21 cycloaddition products was confirmed by N M R and mass spectroscopic analysis. 31P N M R data of the I-phospha-I,3-dienes were obtained.

The Ene Reaction in the Chemistry of Low-Coordinate Phosphorus

“…In this case, propene elimination during flash vacuum thermolysis generates the parent 1-phosphabutadiene 16 (R = H), as well as derivatives bearing only a phosphorus substituent. [26][27][28][29] The highly reactive products 16 could be characterized by IR spectroscopy, MS and PES, as well as by chemical trapping when R = H, Me. 27 In the case of R = t-Bu, Ph, the 1phosphabutadienes 16 were observed by low-temperature 31 P NMR spectroscopy, and were isolated as diphosphacyclohexadiene isomers formed by dimerization in a [4+2] cycloaddition upon warming.…”

Transition structure for the retroene-type elimination reaction of propene from allylamines

“…generation of some carbon-heteroatom double bonds; among these can be cited C‫ס‬O [4][5][6], C‫ס‬S [7,8], C‫ס‬N [9][10][11][12], C‫ס‬Si [13,14], and recently, C‫ס‬P [15,16].…”

Reactivity of allylphosphines with iridium complexes: Diallylphosphines as new bidentate ligands

“…We have reported on the thermal decomposition of allyl and diallylphosphines as a novel way to generate phosphalkene derivatives, via a retroene type of propene elimination involving a six-center transition state [10][11][12][13][14].…”