6533b7d5fe1ef96bd1263b9a

RESEARCH PRODUCT

Reaktionen von Benzothiet mit Iminen

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Reactions of Benzothiete with Imines A great variety of compounds 3a–w containing CN double bonds was studied in the reaction with benzothiete (1). H, alkyl, aryl, OR, SR and NR groups can be attached to the imino function. The azomethines 3a–f, the thiazolines 3g–i, the lactim 3n, the oximes 3r–t, the isoxazolinone 3u and the azine 3v show [8π + 2π] cycloaddition reactions yielding derivatives of 1,3-benzothiazine (4a–i, n, r–v). In the case of 4n, s, t secondary reactions occur, initiated by elimination processes. [8π + 2π] Cycloadditions account also for the reactions 3e 10, 11, 3o 18(I), and 3q 19; however, CC double bonds are representing the 2π component in these examples. The thiazoline 3j and the oxazolines 3k–m afford dibenzo-1,8,4-thiazaundecine derivatives 14j–m, in which two benzothiete units are incorporated. The hydrazone 3w gives the linear adduct 22. Compounds with a heteroaromatic tautomeric form like 3p don't react at all. The reactions of 1 and 3 are very sensitive towards electronic and steric effects and have always to compete with the dimerisation 1 5. Thus, the product yields vary between 90 and 2%.