76202-85-2Relevant academic research and scientific papers
Carbenes, 22. Phosphenes: Trapping Reactions of (Diphenylmethylene)phenylphosphane Oxide by -Cycloaddition with Aldehydes
Regitz, Manfred,Eckes, Helmut
, p. 3303 - 3312 (2007/10/02)
The photolysis of (diazobenzyl)diphenylphosphane oxide (5) in benzene yields the short-lived (diphenylmethylene)phenylphosphane oxide (15) via the carbene 12.The heterocumulene is trapped by aromatic aldehydes, which are added to the reaction mixture, in a -cycloaddition reaction with formation of the 1,2λ5-oxaphosphetanes 16a-e.Carbene reactions with the solvent (formation of the norcaradiene 13) as well as with the trapping reagents (formation of the C/H-insertion products 10a and b) cannot be avoided.With the α,β-unsaturated aldehydes 22a-c, the 1,2λ5-oxaphosphetanes 23a-c are primarily formed.They undergo a complete or a partial photofragmentation to the 1,3-butadienes 24a-c and phenylphosphane dioxide (25).
