ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The condensation of С 3 -С 7 alkyl-and cycloalkylcyclopentanones and cyclohexanones with 1,2-ethane-, 1,2-propane-, and 1,3-butanediols in the presence of heterogenic acid catalysts provided new representatives of spiroacetals. The highest yields of reaction products were obtained in the presence of phosphomolybdic heteropolyacid additionally modifi ed with cobalt and bromine, and also in the presence of the chlorinated cationite KU-23 at 110-130°C. The synthesized spiroacetals possess the jasmine and menthol-wooden fragrance of various tinges.Spiroacetal containing various functional groups alongside the acetal moieties are included into many pharmaceuticals and, соdержащandе наряdу с ацеtальныmand фрагmенtаmand разлandчные фunqцandональные группы, [1], are applied as synthetic fragrant substances [2], solvents for cellulose ethers [3], biologically active preparations in the agrochemistry [4], promising monomers [5], insecticides of high biological destruction [6]. Scarce published papers describe the preparation of spiroacetals from cyclohexanone [7-9] and its derivatives [10] in the presence of homogenic [7-10] and heterogenic catalysts [11]. Yet the information on the synthesis of higher spiroacetals is virtually absent. We formerly developed the ways and processes of the preparation of С 5 -С 7 alkyl-and cycloalkyl-substituted cyclopentanones, cyclohexanones, and a norcamphor [12][13][14].The ketones obtained are analogs of the naturally occurring jasmone and possess odors of jasmine and mentholwooden type with various tinges. Some of them found the application in perfume and cosmetic production [2].This article describes the preparation of higher spiroacetals by the condensation of С 3 -С 7 alkyl-, dialkyl-, and cycloalkyl-substituted cyclanones with 1,2-ethane-, 1,2-propane-, and 1,3-butanediols in the presence of various heterogenic acid catalysts.The following catalysts were used: phosphomolybdic heteropolyacid modifi ed with cobalt and bromine (PMHA) Р 0.17 Mо 2.4 СоBr 0.27 O 6.8 , chlorine-containing cationites KU-2×8 and KU-23, zeocar-2, modifi ed forms of synthetic mordenite (НNaZn-mordenite), and of natural clintoptilolite (Ai-Dag deposit).The yields of spiroethylene-and propyleneacetals of alkyl-, dialkyl-, and cycloalkylcyclanones and the selectivity of the reactions depended essentially on the catalyst nature, structures, and the molar ratio of initial compounds ( Table 1). As seen from Table 1, the most effi cient among the applied catalysts were PMHA modifi ed with cobalt and bromine, chlorinated KU-23 (content of Cl 2.2-9.5%), and НNaZn-mordenite that provided the yields of the corresponding spiroacetals on the level 59-80%.The dependence of the yield of the target product on the ratio of reacting components , temperature, time of the run, and the structure of the initial ketones was monitored by GLC. The reaction proceeds selectively in the medium

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.