Production of S-substituted isothioureas

US4659819A · kind A · utility

Assignees

• Mobay Corporation · US
• BAYER HEALTHCARE LLC · DE

Inventors

• Dennis E. Jackman · Prairie Village, US
• Dietmar B. Westphal · Lenexa, US
• Thomas Schmidt · Neustadt, DE

Key dates

• Filing date: Jul 18, 1984
• Grant date: Apr 21, 1987
• Expiry date: Jul 18, 2004

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D253/07
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

In the production of an S-substituted isothiourea including the function group ##STR1## in which R.sup.1 is an alkyl, alkenyl, aryl or aralkyl radical, wherein a thiourea including the functional group ##STR2## is reacted with an etherifying agent to replace H by R.sup.1, the improvement which comprises effecting the reaction in two steps, in the first step reacting the thiourea material with an etherifying agent including the radical R in which PA1 R is an alkyl, alkenyl aryl or aralkyl radical different from R.sup.1 PA1 thereby to produce the ether ##STR3## and in the second step reacting the ether with a compound of the formula R.sup.1 SH. The process is particularly applicable to the production of the known herbicide ##STR4## from the corresponding thiourea where in the first step methyl bromide or methyl iodide is used to form the S-methyl isothiourea which is then interchanged with ethyl mercaptan. Higher overall yields and/or economies are thereby achieved.