1,2-Benzisoxazoles, synthesis from oximes

A high yielding synthesis of anthranil from 2-nitrobenZaldehyde makes use of zinc and allyl bromide as the reducing agent. The method has also been used for the preparation of 3-substituted anthranils from 2-nitrophenyl ketones <99H(51)1921>. A solid phase synthesis of 3-aminobenzisoxazoles 15 is based on the displacement of fluoride from 2-fluorobenzonitriles by the Kaiser oxime resin and subsequent hydrolysis of the C=N bond <99JOC4547>. A synthesis of 3-(2-dialkylaminoethyl)benzisoxazoles from oximes of 2-hydroxyphenyl ketones has also been described <99H(51)2139>. ... 

As discussed in Section II,D,2, the action of hydroxylamine on o-acylcyclohexanones generally produces an inseparable mixture of 4,5,6,7-tetrahydro-1,2- and -2,1-benzisoxazoles, the latter, except in a few instances, being the major products.92-94,261 Synthesis of 4,5,6,7-tetrahydroanthranils free from contamination by indoxazenes is now possible by condensing esters with 1,4-dianions, e.g., 184, derived from oximes having an a-hydrogen, as exemplified in Scheme 24.262... 

Benzisoxazoles. The reagent is used in a general synthesis of benzisoxazoles from salicylaldehydes. " Salicylaldehyde is treated in ether solution with an excess of the reagent and with anhydrous sodium sulfate the sodium salt of the oxime... 

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