Dimethyl-amino-ethyl methacrylate prodn. - from methyl methacrylate and dimethyl-amino-ethanol using organo-tin cpd. as catalyst

摘要

Prodn. of dimethylaminoethyl methcarylate (I) from methyl methacrylate (II) and dimethylaminoethanol (III) by ester interchange is carried out in the presence of Sn cpd(s). (IV) as catalyst. (IV) have the formula SnR4, R3SnX, R2SnX2, R2Sn A or X'R2Sn-B-SnR2X' (in which each R is 1-12C alkyl or Ph; X is H, -OR, -SR, -S(CH)n-COOR (n = 1 or 2), -OCOR or -OCOCH=CHCOOR. X' is R or X. Y is O or S. A is -COOH=CH-, -CH2OC- or -CH2CH2-, B is -OCOCH=CHCOO, -(OCH2CH2)n-O-, -SCH2CO-(OCH2CH2)n-OCOCH2S-(n = 1 or 2) or -O-). (I) can be used as starting materials for cationic polymers, which are used as antistatics, soil improvers, paper auxiliaries, flocculants, etc. Side reactions e.g. addn. of (III) or MeOH to the double bond, are minimised and (I) can be obtd. in high yield. (IV) do not lose their activity during the reaction, so that only one catalyst addn. is necessary, at the start of the reaction. Unlike the usual catalysts (NaOMe and Ti alcoholates), (IV) are not affected by small amts. of moisture in the system. Many (IV) are readily available in commerce, since they are widely used as stabilisers for PVC or (starting materials for) pesticides.