Arbuzov photo-rearrangement

Bentrude et al. [20] reported the first photo-Arbuzov rearrangement of arylethylphosphites (Scheme 4). The direct photolysis of arylethylphosphites... 

Scheme 5 Photo-Arbuzov rearrangement of arylethylphosphites via a short-lived singlet proximate radical pair mechanism. Reprinted with permission from [22]. Copyright 2001 American Chemical Society...

The photo-Arbuzov rearrangement of allyl-, benzyl- and naphtylmethyl-phosphites (Scheme 13), first developed by Bentrude et al. [20], found applications in the preparation of phosphonates (70-90%) [38]. Arylphosphonates have been shown to act as protein tyrosine kinase inhibitors [39] or non-hy-drolyzable analogs of phosphorylated tyrosine residues [40]. 

The Michaelis-Arbuzov reaction may be photoinitiated with appropriate sub- strates such as tetrahalomethanes and aryl iodides suitable phosphites undergo photo-Arbuzov rearrangement (see below). 

The photo-Arbuzov rearrangement of allylic52 and benzylic53 phosphites has been developed by Bentrude and co-workers, see, for example, Scheme 12. These reactions are completely regioselective for the benzyl and allyl groups and have been employed in synthesis (the requisite phosphites being obtained by standard methods).54... 

Bhanthumnavin, W., Bentrude, W. G. Photo-Arbuzov Rearrangements of 1-Arylethyl Phosphites Stereochemical Studies and the Question of Radical-Pair Intermediates. J. Org. Chem. 2001, 66, 980-990. 

A paper on new approaches to the generation of arylphosphinidenes has been published. The stable bis-azide precursor (133) upon photolysis, or vapour phase thermolysis, gave (134), obviously via the phosphinidene (135) the same product was obtained by photolysis of the phosphaketene (136). The reduction of aryldiazonium salts to arenes with triethyl phosphite or triphenylphosphine is shown to proceed by a radical-chain mechanism. The previously described photo-Arbuzov rearrangement of benzyl phosphites has been used to prepare several acyclic phosphonate nucleotide analogues, e.g. (137). ... 

This reaction has been extensively modified. Besides the ruthenium-catalyzed, metal-centered radical or photo-Arbuzov rearrangements as described earlier, alkyl halides have been replaced by metal halides (e.g., NiC ), trimethylsilyl chloride (TMSCl), and organometallics. 

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