3656c.     ---------------.  [STERNBERG, H. W., WENDER, I., FRIEDEL, R. A., AND ORCHIN, M.]  Chemistry of the Metal Carbonyls.  III.  Reaction Between Dicobalt Octacarbonyl and Dimethylamine.  Jour. Am. Chem. Soc., vol. 75, 1953, pp. 3148-3152.

          It has been shown that many Lewis bases react with dicobalt octacarbonyl:  3[Co(CO)₄]₂+12B→2[Co(B)₆]**[Co(CO)₄]+8 CO.  When excess dimethylamine is condensed into dicobalt octacarbonyl at -80° and the solution is warmed to room temperature, no CO is evolved and equimolar amounts of Co cation and Co carbonyl anion are formed.  Infrared and mass spectrometric analysis of the reaction product indicated the presence of dimethylamine, dimethylformamide and small amounts of tetramethyl urea.  It appears from these data that the CO usually given off in the disproportionation of dicobalt octacarbonyl in this instance reacted with the amine:  3[Co(CO)₄]+20(CH₃)₂NH→2[Co[(CH₃)₂NH]₆]⁺⁺[Co(CO)₄]-₂+8(CH₃)₂NCHO.  According to this equation, stoichiometric quantities of dicobalt octacarbonyl would be required to convert dimethylamine to dimethylformamide.  However, if it were possible to reverse the first equation employing the proper conditions, only catalytic quantities of dicobalt carbonyl might be required to convert dimethylamine to dimethylformamide, especially since the latter can coordinate the cation in the form [Co[(CH₃)₂NCHO]₆]⁺⁺.   Treatment of dimethylamine with 1 mole % of dicobalt octacarbonyl at 200°-210° and an initial pressure of 3000 p.s.i. of CO gave dimethylformamide smoothly and in good yield; no tetramethyl urea was formed.  A possible mechanism for the formation of dimethylformamide from dimethylamine and dicobalt octacarbonyl is discussed.

          WENDER, I., GREENFIELD, H., METLIN, S., AND ORCHIN, M.  Chemistry of the Oxo and Related Reactions.  VI.  Experiments With Meta- and Para-Substituted Benzyl Alcohols.  See abs. 3655b.