Dipole moments methylamine

Make a three-dimensional drawing of methylamine, CH3NH2, a substance responsible for the odor of rotting fish, and show the direction of its dipole moment fJL = 1.31). 

Methylamine contains an electronegative nitrogen atom with two lone-pair electrons. The dipole moment thus points generally from -CH3 toward NH2. 

Methyl thioacetnte, electrostatic potential map of, 791 9-Methyladenine. electrostatic potential map of, 1121 Methylamine, bond angles in. 19 dipole moment of, 39 electrostatic potential map of, 56, 922... 

TABLE 1. Calculated (MM2, MM3 and ab initio) and observed structural parameters for ammonia and methylamines (bond lengths in A, bond angles and tilt angles in degrees, dipole moments in Debye)5,6. Reprinted with permission from Refs. 5 and 6. Copyright (1985, 1990) American Chemical Society... 

Data on molecules containing nitrogen, oxygen, silicon, phosphorous and sulfur not only provide additional examples, but also allow assessment of the ability of the different models to reproduce known changes in dipole moments accompanying structural variations. For example, dipole moments in methylamines are known experimentally to decrease with increasing methyl substitution,... 

Moreover, the inductive contribution of a p deuterium to the IE on amine basicity was estimated.31 The inductive effect on pK due to an sp2-sp3 C-C bond, with a dipole moment of 0.35 D, as in propene, can be assigned as 0.95, the ApAf between allylamine and methylamine. Above, in connection with the structural question of the extent to which IEs affect dipole moments, dCu dco is 0.5 pm and dfi/dd is 0.004e. These combine to a ApAT on deuteration of 0.001, which is much smaller than the measured IEs in Table 5. An inductive contribution does exist, but it is negligible. 

Faraday Soc. 43, 374—93 (1947). Dipole moment NHs, methylamines, gas, liquid, benzene solution. 

Mobile, hygroscopic liquid. Characteristic amine odor-mp -4.9". bp7H) 128.9s bp( 20.0". df 1.007. ng 1.4540. Volatile with steam. Does not form an azeotrope with water. Flash pt, open cup 100 i (38"C), Surface tension at 20 = 37,5 dynes/cm. Viscosity at 20" = 2.23 cp. Dipole moment l. 58. Strong base, pKb 5.6. Corrosive to human skin. Miscible with water with evolution of some heat. Immiscible with coned NaOH solns. Also miscible with acetone, benzene, ether, castor oil, methanol, ethanol, ethyl ene glycol, 2-hexanone, linseed oil, turpentine, pine oil. Will dissolve 109% dimeihylamine 34% trimethylamine 33% methylamine > 5% naphtha < 1% paraffin oil < 5% sulfur. LDm orally in female rats l.05 g/kg, Smyth et al. Arch. 

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