Group migration 1.5- phenyl

The effect of substrate structure on product profile is further illustrated by the reactions of cis- and trons-stilbene oxides 79 and 83 with lithium diethylamide (Scheme 5.17) [32]. Lithiated cis-stilbene oxide 80 rearranges to enolate 81, which gives ketone 82 after protic workup, whereas with lithiated trans-stilbene oxide 84, phenyl group migration results in enolate 85 and hence aldehyde 86 on workup. Triphenylethylene oxide 87 underwent efficient isomerization to ketone 90 [32]. 

In this reaction para-xenyl and a-naphthyl groups migrate six times as readily as competing phenyl or para-tolyl groups.111... 

In yet another facet of heterocubane chemistry, 14 (R = Ph) has been found to react with Ag+ in acetonitrile to form the salt (MeCN)3Rh(C4H4B-Ph)+ BF4 20, which in turn combines with arenes to generate (arene)Rh(C4H4B-Ph)+ BF4- products.9 Under vacuum, 20 loses MeCN to form the polymer 21, the phenyl group migrating to the Rh center of a different fragment. 

Phenyloxirane-2-carboxylates undergo phenyl group migration to give 3,3-difluoro-2-phenylpropanoic esters, e.g. 4,181 and 2-aryloxiranes are converted into l,l-difluoro-2-phenyl-ethanes 5 as the sole product.182... 

In a reaction, the mechanism of which bears a close analogy with that shown for the phenyl group migration in Scheme 18, ethyl 3-methylindole-2-carboxylate is converted by sulfuryl chloride into ethyl 3-methyl-2-oxoindoline-3-carboxylate (79JCS(P1)595). 

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