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Product composition and a d 1 and P-d3 isotope effects in the solvolysis of neomenthyl tosylate (8-OTs) were determined in 70% aqueous trifluoroethanol and 70% aqueous ethanol. Both trifluoroethanolysis and ethanolysis gave I-2% neomenthol(97% d3), 12-13% cis-4-menthanol(l00% d3), 2-3% trans-4-menthanol(lOO% d3), 66-70% 3-p-menthene (83% d3 and 17% dz), and 5-9% 4,8-p-menthene (97% d3), respectively. These results and the high value of the P-d3 isotope effect ( k H / k D = 2.45) were interpreted in terms of rate-determining hydride shift followed by elimination which accounts for 75% of all products. In 85% of the elimination products the migrating hydrogen (deuterium) is not the one being eliminated.Axial cyclohexyl derivatives such as neomenthyl tosylate (8-OTs) yield, under solvolytic conditions, predominantly elimination products.' The antiperiplanar arrangement of the leaving group and the axial tertiary P-hydrogen atom provide the ideal geometry for hyperconjugation and hydrogen participationa2 It has been shown that both of these interactions can be conveniently studied by means of secondary deuterium isotope e f f e~t s .~ Previous studies of the solvolysis of unlabeled derivatives4+ could not provide satisfactory answers to questions regarding the participation of neighboring hydrogen in the rate-determining step (possibly via a bridged intermediate) and the fate of this hydrogen in the (subsequent) elimination reaction. Therefore, we considered it of interest to perform a detailed kinetic and product study of the solvolysis of neomenthyl tosylate (8-OTs) and its specifically deuterated analogues 6-OTs and 3-OTs. The synthesis of this material as well as of 3-p-menthene (10) and 2-p-menthene (ll), respectively, and the isomeric cis-and tram-6menthanols (12 and 131, which were needed for the purpose of identification and product characterization, is given in Schemes

The syntheses of 1-3, KOPiv, and AgOPiv are described in our earlier paper. NaOPiv, LiOPiv and Et4NOPiv were prepared in the same way as was KOPiv. In the same paper are described the reactions of 1 with the pivalate salts and the NMR analysis of the products.

The reaction of 2,4,5-triphenyl-3H-pyrrol-3-one I-oxide with dimethyl acetylenedicarboxylate gave pyridine 9a, 4(3H)-pyridone loa, isoxazolidine 11, and traces of pyridone 13. Pyridone 10a is not an intermediate in the formation of 9a, yet on photolysis or pyrolysis above its melting point, loa yielded pyridine 9a. Possible reaction mechanisms that rationalize the formation of these products are discussed.