Tetramethylguanidine

N,N,N',N' -Tetramethylguanidine (TMG) [80-70-6], C5H13N3, Mr 115.18, is a stable, unusually strong base, pKa 13.6 (25 ℃), with a free imino group. It is a colorless to light-yellow liquid, miscible with water and common organic solvents: 0.92 g/cm3 (25 ℃), bp 160 ℃, vapor pressure 0.03 kPa (25℃).

Base employed in the preparation of alkyl nitriles from alkyl halides and 3′-alkylthymidines from 3′-nitrothymidines.

1,1,3,3-Tetaramethylguanidine is used as a strong, non-nucleophilic base for alkylations in organic synthesis. 1,1,3,3-Tetramethylguanidine is an efficient and selective catalyst for the benzoylation of alcohols.

Tetramethylguanidine (TMG) is used as polyurethane foam catalyst, as accelerator for the syntheses of polysulfured rubber, as a strong base in the photochemical (e.g. couplers) and in the pharmaceutical (e.g. steroids) industries. Product Data Sheet

Flammable

Prepared from cyanogen chloride and dimethylamine in a 1 : 2 molar ratio, TMG is used as a polyurethane foam catalyst, in the preparation of pigments for color photography, and in steroid synthesis. 

Reflux it over granulated BaO, then fractionally distil it. Protect it from CO2. [Beilstein 4 IV 227.]