Dimethylamine, rotational barrier

Several calculations on amino and nitro compounds were performed as part of the validation of Tripos 5.252. Thus, the rotational barriers in methylamine and dimethylamine were calculated to be 2.8 and 4.9 kcalmol-1, respectively, in fair agreement with experiment (2.054 and 3.654 kcalmol-1, respectively), and the A-value of the nitro group was calculated to be 0.6 kcalmol-1, only about half of the experimental value... 

Rotational barriers. All the force fields examined here reproduce the experimentally observed increase in the rotational barrier on going from methylamine to dimethylamine and, in particular, MM2 and DREIDING do a good job in matching the experimental data. 

The bis(tetiafluoroethyl) ethers obtained by reacting polyethyleneglycol with tetrafluoroethylene have useful surface activity. 1 The preparation of aminoacetals of the type (CF3)2C C(NMes)OAr, by the successive reaction of the sodium salt of a phenol and then of dimethylamine with perfluoroisobutene has been described i in the compound (CFs)2C C(NMea)OMe, the CF3 groups are equivalent on the n.m.r. timescale at low temperatures, indicating a low barrier to rotation about the C=C bond. A number of fluorocarbon epoxides have been prepared... 

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