Fert-Butyl carbamates

The preparation of fert-butyl carbamates 782 with B0C2O, and their one-pot conversion to amides 783 with an acyl halide/methanol mixture, has recently been reported [567]. 

The Boc group is easily cleaved by brief treatment with trifluoroacetic acid (TFA), CF3COOH. Loss of a relatively stable ferf-butyl cation from the protonated ester gives an unstable carbamic acid. Decarboxylation of the carbamic acid gives the deprotected amino group of the amino acid. Loss of a proton from the fert-butyl cation gives isobutylene. 

Ethoxypyrrolin-5-one l-Pyrrolin-5-one, 2-ethoxy- (8) 2H-Pyrrol-2-one, 5-ethoxy-3,4-dihydro- (9) (29473-56-1) ferf-Butyl N-(l-ethoxycyclopropyl)carbamate Cyclopropanecar-bamic acid, 1-ethoxy-, fert-butyl ester (8) Carbamic acid, (1-ethoxycyclopropyl)-, 1,1-dimethylethyl ester (9) (28750-48-3 41879-49-6)... 

Carbamate, N-vinyl-, fert-butyl Vinyl acetate 0.46 0.03 1.12 0.07 N 827... 

This dimer reacts as two molecules of free 5-feit-butyl-isoxazolyl-3-isocyanate with secondary amines or with alcohols to give the corresponding ureas or carbamates. These are useful as agrochemicals or as intermediates for fine chemicals, e.g. 3-(5-fert-butylisoxazolyl)-l,1-dimethyl urea (common name Isouron), which is useful as a herbicide for sugar cane and other crops [216]. 

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