1, 1-Cyclopentyl dimethanoldimethyl ether was synthesized from diethyl malonate and 1,4-dibromo butane by alkylation, ester reduction and etherification. The key factors affecting reactions were studied and the optimal reaction conditions were found as follows: (1) for alkylation, using CsOH as catalyst,n(diethyl malonate) s n(CsOH) '· n(1,4-dibromo butane) = l. 0 : 2. 2 : 1. 4,the yield of cy-clobutane-1,1-dicarboxylic acid diethyl ester was 93. 0//o?(2)for ester reduction,using anhydro-ZnCl2 as catalyst,M(cyclopentyl-l,l-dicarboxylic acid diethyl ester) ? ?(KBH4) = 2. 0 ! 1.0,the yield of 1,1-cy-clopentyl dimethanol was 88. 1%; (3)for etherification,using tetrabutyl ammonium bromide as catalyst, n(l,l-cyclopentyl dimethanol) : w(NaOH) '·n(dimethyl carbonate) = 1. 0 ! 8. 0 : 2. 4,the yield of 1,1-cyclopentyl dimethanoldimethyl ether was 61. 2%.%以丙二酸二乙酯和1,4-二溴丁烷为起始原料,经烷基化、酯还原和醚化反应合成环戊基-1,1-二甲醇二甲醚,分别考察关键因素对3步合成反应的影响.适宜的工艺条件为:①烷基化反应时,n(丙二酸二乙酯)；n(CsOH)∶n(1,4二溴丁烷)=1.0∶2.2 ∶ 1.4,CsOH为催化剂,环戊基-1,1-二甲酸二乙酯的收率为93.0％；②酯还原反应时,以无水ZnCl2为催化剂,n(环戊基-1,1-二甲酸二乙酯)∶n(KBH4)=2.0∶1.0,环戊基-1,1-二甲醇的收率为88.1％③醚化反应时,以四丁基溴化铵为催化剂,n(环戊基-1,1-二甲醇)∶n(NaOH)∶2(碳酸二甲酯)=1.0∶8.0∶2.4,环戊基-1,1-二甲醇二甲醚的收率为61.2％.
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