METHOD FOR SYNTHESIZING 2,7-DIMETHYL-2,4,6-OCTATRIENE-1,8-DIALDEHYDE

摘要

Provided in the present invention is a method for synthesizing 2,7-dimethyl-2,4,6-octatriene-1,8-dialdehyde. The synthesis method comprises the following steps: (1) adding acetaldehyde diethyl acetal and ethyl-(1-propenyl)-ether under the effect of a catalyst to produce 1,1,3-triethoxy-2-methyl-butane; (2) pyrolysis synthesizing 1,1,3-triethoxy-2-methyl-butane under the catalytic effects of isoquinoline and p-Toluenesulfonic acid to produce 1-methoxy-2-methyl-1,3-butadiene; (3) dissolving 1-methoxy-2-methyl-1,3-butadiene in anhydrous ethanol solvent for synthesis with a phase transfer catalyst, cetyl-trimethyl ammonium bromide, and a chlorinating agent, trichloroisocyanuric acid, to generate 4,4-diethoxy-3-methyl-1- chloro-butene; (4) combining 4,4-diethoxy-3-methyl-1-chloro-butene with a triphenylphosphine salt to produce a phosphonium salt; and (5) condensing the phosphonium salt under the effects of hydrogen peroxide in conjunction with sodium carbonate solution to generate 1,1,8,8-tetramethyl-2,7-dimethyl-2,4,6-octatriene; then hydrolyzing under acidic conditions to synthesize 2,7-dimethyl-2,4,6-octatriene-1,8- dialdehyde. The present invention has a simple process route, is easy to operate, and has mild conditions, great yield, and great industrial value.