Diethylthiambutene (Thiambutene, Themalon, Diethibutin, N,N-Diethyl-1-methyl-3,3-di-2-thienylallylamine) is an opioidanalgesic drug developed in the 1950s[1] which was mainly used as an anesthetic in veterinary medicine and continues, along with the other two thiambutenes dimethylthiambutene and ethylmethylthiambutene to be used for this purpose, particularly in Japan.[2][3] It is now under international control under Schedule I of the UN Single Convention On Narcotic Drugs 1961, presumably due to high abuse potential, although little more information is available. It is listed under Schedule I of the US Controlled Substances Act as a Narcotic and has an ACSCN of 9616 with zero annual manufacturing quota as of 2013.
The conjugate addition of diethylamine [109-89-7] to ethyl crotonate [623-70-1] [10544-63-5] (1) gives ethyl 3-(diethylamino)butanoate, CID:10679145 (2). Addition of two equivalents of 2-thienyllithium to the ester gives the tertiary alcohol [94094-46-9] (4'). The dehydration of this then completes the synthesis of diethylthiambutene (5').
↑Adamson, D. W. (1950). "180. Aminoalkyl tertiary carbinols and derived products. Part II. 3-Amino-1 : 1-di-2′-thienyl-alkan-1-ols and -alk-1-enes". J. Chem. Soc. 0 (0): 885–890. doi:10.1039/JR9500000885.
