13 C NMR study of 7, 7-disubstituted quinone methides

…, B Koutek, L Pavlíčková, M Souček

Index: Lycka, Antonin; Snobl, Dobroslav; Koutek, Bohumir; Pavlickova, Libuse; Soucek, Milan Collection of Czechoslovak Chemical Communications, 1981 , vol. 46, # 9 p. 2083 - 2090

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Citation Number: 3

Abstract

Abstract Carbon-13 chemical shift assignments for nine 7, 7-disubstituted 2, 6-ditert- butylquinone methides of the types III-VI are reported. The 13 C shifts of the exocyclic double bond carbon atoms are extraordinarily sensitive to C (7) substitution, viz. ΔδC (7)= 82.4 ppm and ΔδC (4)= 56.7 ppm on going from the dimethylamino to the cyano substituent. In contrast, electronic properties of the substituents are only weakly expressed on the ...