Nitrosocarboxylic acid esters

TiCl4 added dropwise to a stirred soln. of startg. O-silyl O-alkyl keteneacetal and isoamyl nitrite in methylene chloride at 10°, and stirring continued at room temp, for 24 h ethyl a-oximinopropionate. Y 65%. O-Silyl O-alkyl keteneacetals not possessing an a-hydrogen gave a-nitrosocarboxylic acid esters. F.e. and with nitric oxide s. S.M. Ali et al., Synthesis 1988, 805-6. 

Hydroxy-o-nitrocarboxylic acid esters from cyclic o-nitroacetals via 2-hydroxy-o-nitrosocarboxylic acid esters Partially protected carbohydrate derivs. 

Azohydroperoxides O-Carbamylhydroxylamines Carbazic acid esters Hydrazoformic acid esters N-Hydroxyureas N-Nitrimines N-Nitrosoacylamines N-Nitrosocarboxylic acid amides 20 Nitrosolic acids... 

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