Abstract: The combined action of a donor and acceptor substituent on the rotational barriers in syn-1-cyano-anti-1-methoxyallyl radical and anti-1-cyano-syn-1-methoxyallyl radical (E,= 6.0 f 0.4 and 6.1 f 0.6 kcal/mol, respectively) has been evaluated via ESR spectroscopy. Comparison of these values with the rotational barriers in 1-deuterioallyl radical (15.7 f 1.0 kcal/mol), 1-cyanoallyl radicals (10.2 f 0.9 kcal/mol), and 1-methoxyallyl radicals (14.5 f 1.1 ...
