Synthetic method of pesticide dinotefuran intermediate 3-hydroxymethyl tetrahydrofuran

The invention discloses a synthetic method of pesticide dinotefuran intermediate 3-hydroxymethyl tetrahydrofuran, and the synthetic method is as follows: reacting compound succinic acid dialkyl ester with formic acid alkyl ester in the presence of a strong alkali to obtain a compound III, then obtaining a compound II by a reduction reaction, finally, in the presence of an acid catalyst, obtaining a compound shown as formula I by a dehydration cyclization reaction, and R or R ' respectively independently represents C1-5 alkyl. The synthetic method is low in raw material cost, simple in reaction operation, less in pollution, high in yield of each step, 99% in the yield of the reducing step, and suitable for industrial production.