Benzils monooxime

Examples of scission of bonds separated from the carbonyl group by a double bond or an aromatic ring are also known. Thus, the benzil monooxime (69) undergoes y-scission (Scheme 3.50) (possibly by consecutive a- then 3-scissions). 

The treatment of aliphatic monoamines, benzil monooxime, benzil monohydrazone, and alkyl, monohaloalkyl arylketoximes bearing two or three a-hydrogens with tetrasulfur tetranitride to afford 1,2,5-thiadiazoles was presented in CHEC(1984) and CHEC-II(1996). 

SYNS a-BENZIL MONOOXIME BENZIL, MONOXIME BENZIL, MONOOXIME BENZIL, 3-MONOXIME BENZIL, OXIME 1,2-DIPHENYL-ETHANEDIONE MONOXIME ETHANEDIONE, DIPHENYL-, MONOOXIME... 

BENZILATE DU DIETHYLAMINO-ETHANOL CHLORHYDRATE (FRENCH) see BCAOOO BENZILE (CLORURO di) (ITALIAN) see BEE375 BENZILIC ACID-P-DIETHYLAMINOETHYL ESTER HYDROCHLORIDE see BCAOOO BENZIL, MONOOXIME see BCA300... 

The third reaction type to be discussed in this section is the Forster reaction. It was discovered by Forster in 1915, as he had obtained (benzoyl)(phenyl)diazomethane (2-diazo-l,2-diphenylethan-l-one, 2.62) by treatment of (Z)- and ( )-benzil monooxime ((Z) = 2.95) with sodium hypochlorite and ammonia (which readily forms chloramine). a-Keto-monoximes like 2.95 are obtained easily from a-methylene-con-taining ketones (e.g., 2.94) by the oximation reaction, i.e., a nitrosation with a nitrous acid ester followed by a C O proton shift (2-41). 

Bravo et al. studied the reaction of various ylides with monooximes of biacetyl and benzil. Dimethylsulfonium methylide and triphenylarsonium methylide gave 2-isoxazolin-5-ol and isoxazoles, with the former being the major product. Triphenylphosphonium methylide and dimethyloxosulfonium methylide gave open-chain products (Scheme 135) (70TL3223, 72G395). The cycloaddition of benzonitrile oxide to enolic compounds produced 5-ethers which could be cleaved or dehydrated (Scheme 136) (70CJC467, 72NKK1452). 

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