Acylamines, 2-functionalized

The photocyclization of 3-nitro-2-pyridyl-DL-leucine (354) to 2-isobutyl-imidazo[4,5-i]pyridine (355) has been studied spectrophotometrically and the quantum yield of the reaction determined as a function of pH (72JCS(P2)2218). 3-iV-Methanesul-fonamidopyridine 1-oxide (356) is acylaminated at C-2 by phenylbenzimidoyl chloride (357) and the intermediate 2-acylaminated product (358) cyclized to 2,3-diphenyl-imidazo[4,5-i]pyridine (359) (74JOC1802). 

The next part is devoted to the D-fructosylamines the substituted amino function includes acyl- as well as aryl-amines, and even amino acids. At the time of the previous review,principally acylamines had been synthesized, but the mechanism of formation has since been elucidated, and it thus became possible, by adjusting the reaction medium, to obtain higher yields and crystalline derivatives. 

Examples of cyclizations of the following pairs of functions are also described acylhydrazine- imine, acylamine-alkoxyamine and acylamine-imine. 

The following pairs of functional groups are also mentioned in this chapter carbamate and methylene, acylamine or carbamate and trimethylsilylmethyl, alkene and tosylamino, alkyne and imine. 

Hydrozirconation. Hydrozirconation of nitriles by Cp2Zr(H)Cl followed by reaction with RCOCl and quenched with nucleophiles gives rise to functionalized amides such as acylaminals and acyl hemiaminals (by adding alcohols and water, respectively). ... 

A soln. of 7,10-trans -2,6-epi-7-isopropenyl-10-methyl-4-oxotricyclo[4.4.0.0b5]de-cene-2-carboxylic acid in acetic acid triethylamine-tert- hut2Lno electrolyzed 20 hrs. at 10° with Pt-electrodes at a constant current of 0.08 amp./cm2 and ca. 20 V. -> 7,10-rrfln5--2,6-epi-2-acetoxy-7-isopropyl-10-methyltricyclo[4.4.0.0l 5]decan-4-one. Y 72%. - Under the above conditions, hydrogenation of the isopropenyl function occurs spontaneously. S. Torii and T. Okamoto, Bull. Chem. Soc. Japan 49, 111 (1976) 1-acoxy-l-acylamines by decarboxylative acoxylation s. T. Iwasaki, et al., J. Org. Chem. 42, 2419 (1977). 

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