2-Phenyl sulphanyl and sulphonyl propane cpds. prodn. from thiophenol - by chlorination with chlorine@ addn. of allyl cpd. and opt. oxidn. with hydrogen peroxide

摘要

Prodn. of 2-phenylsulphanyl- and 2-phenylsulphonyl-propane cpds. (I) and 2-(3-nitrophenylsulphonyl)-propane cpds. (II) of formulae (I) and (II) (where R is a (substd.) alkyl or aryl gp. or pref. H; Y is a substit. eliminated by alkali to form the vinyl gp.; x is 0 or 2) involves (a) reacting thiophenol (III) with Cl2 to give a phenylsulphenyl chloride (IV); (b) adding an olefinic cpd. of formula Y-CH2-CH=CH-R (V); (c), for (I) with x = 2, oxidising (I) or with x = 0, with H2O2; and (d), for (II), nitration in the usual way. USE/ADVANTAGE - (I) are intermediates, esp. for the synthesis of reactive dyestuffs. They are prepd. using readily available Cl2 and H2O2, rather than N-chlorosuccinimide and m-chloro-perbenzoic acid, avoiding the formation of by-prods. which are difficult to separate. In an example, 709 pts.wt. Cl2 were passed into a soln. of 2204 pts. (III) in 8070 pts. dry chlorobenzene (VI) under N2 at 0 deg. C, in ca. 3 hrs. The charge was stirred for 30 mins., then excess Cl2 was expelled with dry N2. The charge was cooled to -40 deg. C, then 1680 pts. allyl chloride were added slowly at a constant rate in ca. 30 mins. Stirring was continued for 45 mins, then the charge was warmed to 20 deg. C and (VI) was distilled off in-vacuo to give 4370 pts. 1,3-dichloro-2- (phenylsulphanyl)- propane as a light yellow oil which distilled at 95 deg. C/0.2 mbar.