Diethyl Sulfate → Eptam

Participants

Reaction Conditions

Reaction Steps

94.5 g. (0.5 moles) of O-ethyl N,N-dipropyl-thiocarbamate are introduced into a 250 ml. round-bottomed flask, and 4.7 g. of diethyl sulfate are added. The mixture is refluxed for 80 minutes on an oil bath heated to 160°C. The progress of the reaction is monitored by sampling the reaction mixture and recording the UV spectra of the samples in methanol. The absorption maximum at 250 nm, characteristic of the =S group of the starting substance, gradually decreases, and disappears when the isomerization is completed. Then the reaction mixture is cooled, and the small amount of oily substance separated at the bottom of the flask is removed. The upper phase is distilled in vacuo. The title compound boils at 122°-124°C/19 Hgmm. 86.0 g. (91 %) of S-ethyl N,N-di-propyl-thiocarbamate are obtained; nD 30 = 1.4750.

Provenance & Evidence