NMR Experiments on acetals. XXXVIII. The conformational equilibrium in trans??4, 5, 5??trimethyl??6??alkyl??1, 3??dioxanes

D Tavernier, M Anteunis

Index: Tavernier,D.; Anteunis,M. Bulletin des Societes Chimiques Belges, 1973 , vol. 82, p. 405 - 411

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Citation Number: 3

Abstract

Abstract The chair-chair equilibrium in trans-4, 5, 5-triMe-6-alkyl-1, 3-dioxanes (alkyl= Et, n. Pr, i. Bu, neoPe, i. Pr and Ø) has been studied by the slow exchange NMR shift method. The conformer with equatorial alkylgroup is the more stable one, free energy differences δG 186 (cal/mole) being: 70 (Et), 84 (n. Pr), 10 (i. Bu), 506 (neoPe), 674 (i. Pr) and> 1 000 (ø).