(f)Steric crowding increases more when hydroxide adds to the axial carbonyl group.20.32Compound A is thep-toluenesulfonate ester (tosylate) oftrans-4-tert-butylcyclohexanol. Theoxygen atom of the alcohol attacks the sulfur ofp-toluenesulfonyl chloride, and so the reactionproceeds with retention of confguration.The second step is a nucleophilic substitution in which benzoate ion displaces p-toluenesulfonatewith inversion of confguration.Saponifcation of cis-4-tert-butylcyclohexyl benzoate in step 3 proceeds with acyl–oxygen cleav-age to give cis-4-tert-butylcyclohexanol.20.33Reaction of ethyl triFuoroacetate with ammonia yields the corresponding amide, compound A. Com-pound A undergoes dehydration on heating with P4O10to give triFuoroacetonitrile, compound B.Grignard reagents react with nitriles to form ketones.tert-Butyl triFuoromethyl ketone is formedfrom triFuoroacetonitrile by treatment withtert-butylmagnesium chloride followed by aqueoushydrolysis.
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This note was uploaded on 09/30/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.