The strain energy for methylenecyclohexane has been calculated to be 4.5 kcalmol−1using estimations for 1,3-diaxial strain (0.9 kcalmol−1), methyl/hydrogen allylic strain (1.3kcalmol−1), and methyl/methyl allylic strain (7.6 kcalmol−1) values.[2] The strain energy in 1,8-...
Our results demonstrate that absent pseudoallylic strain, a 1,3-diaxial interaction of an amide with a carboxylic acid leads to only a 2400-fold increase in the rate of amide bond cleavage as compared with the rate of hydrolysis of an unactivated peptide bond....
(75%:25%; ΔG° = 0.42 kcal mol−1) with a preference for the diaxial conformer was found, due to the anomeric effect which also dominates the conformational equilibrium of 3-methoxy-1,2,4,5-tetroxane; the axial conformer was found, in agreement with the X-ray structure <1998AHC(...