Michael J. Y. Chen, J. Linehan, J. W. Rathke
May 11, 1990
Citations
0
Influential Citations
8
Citations
Journal
Journal of Organic Chemistry
Abstract
The autoxidation of trimethylamine in aqueous solutions has been studied at 100C and at O{sub 2} pressures up to 153 atm. Trimethylamine N-oxide is a major product. Its yield accounts for as much as, but never in excess of 50%, the balance being Me{sub 2}NH and HCONMe{sub 2}. The reaction follows second-order kinetics, -d(Me{sub 3}N)/dt = k(Me{sub 3}N)P{sub o{sub 2}}, where k = 8.7 {times} 10{sup {minus}7} atm{sup {minus}1} sm{sup {minus}1}. In solutions buffered with 0.1 N NaOH, the yield of Me{sub 3}NO is reduced. These results are interpreted in terms of a rate-limited electron-transfer reaction between Me{sub 3}N and dioxygen, followed by reactions dictated by the radical ions, Me{sub 3}N{sup {sm bullet}+} and O{sub 2}{sup {sm bullet}{minus}}, thus generated. It is noted that only one oxygen atom in the O{sub 2} molecule is incorporated into Me{sub 3}NO, the other being used in the sacrificial oxidations to give other products.