Preparation and Steric Structure of 3(2H)-Pyridazinones and 1,2-Oxazin-6-ones Fused with Three- to Six-membered Saturated Carbocycles or Norbornane Skeleton

Article abstract of DOI:10.1007/BF00812708

Reactions of cis-2-(4-methylbenzoyl)-cyclopropane- (1) and -cyclobutanecarboxylic acids (2), the stereoisomeric cyclohexyl homologues (3 and 4), and di-endo-3-(4-methylbenzoyl)-bi-cyclo<2.2.1>heptane-2-carboxylic acid (5) with hydrazines yield the cycloalkane-condensed 3(2H)-pyridazinones 6-9 and the norbornane di-endo-fused derivatives 10.With hydroxylamine, compounds 1 and 3-5 were transformed to the cycloalkane- and norbornane-condensed 1,2-oxazin-6-ones 11-14.Transformation of 3-5 led to the trans-hexahydroanthrone 17a and its methylene-bridged analogue 24.From the stereoisomeric hexahydro-1(3H)-isobenzofuranones 20 and 21, the partly saturated anthrones were also prepared; the products (16b and 17b) contain the methyl substituent in position 6.On reduction, 16b yield the 2-methyloctahydroanthracene 22.The structures of the compounds were proved by 1H and 13C NMR spectroscopy, making use of NOE, DEPT, and CH-COSY techniques. - Keywords: Cycloalkanes; Heterocycles; Friedel-Crafts acylation; Isomerization; Methyloctahydroanthracen-9-ones; Reduction; LAH/AlCl3.