| 摘要 |
FIELD: organic synthesis catalysts. ^ SUBSTANCE: invention is dealing with preparation of homogenous catalyst for production of acrylic acid esters according to metathesis reaction of malates with ethylene. Two variants of preparing catalyst are developed. In particular, catalyst of general formula , wherein A1, A2 represent chlorine, L dihydroimidazole ligand, R1, R2, R3, the same or different, are substituents selected from hydrogen, alkyl, trialkylsylyl, and alkoxy; and catalyst of formula are proposed. Use of these catalysts allows number of cycles of metathesis reaction of dialkyl malates with ethylene to be increased both under moderate temperature (about 50C) conditions when reaction is carried out without distillation of product and at temperatures about 120C when acrylate produced is distilled out of reaction mixture. Catalytic composition is further developed allowing not only number of reaction cycles but also catalyst lifetime to be increased. Such composition contains indicated catalyst and 2-isopropoxystyrene or its derivative at molar ratio 1:(5-500), respectively. ^ EFFECT: increased catalyst activity and lifetime. ^ 7 cl, 4 tbl, 28 ex |
