光学材料中间体DADMNS的合成研究

Synthesis of intermediate DADMNS for optical materials

系统研究了二阶非线性光学材料中间体E-2,5-二乙酰氨基-2',4'-二甲氧基-4-硝基二苯乙烯(DADMNS)的合成。以2,5-二氨基甲苯(2,5-TDA)为原料,经过乙酰化和硝化得到2,5-二乙酰氨基-4-硝基甲苯(DANT),采用1,3-二甲氧基苯经Vilsmeier-Haack反应制备2,4-二甲氧基苯甲醛(DMBA)。DANT与DMBA在哌啶为催化剂,DMSO为溶剂,分子筛作脱水剂的条件下缩合得到目标产物DADMNS,收率为73.20%,精制后HPLC检测纯度为98.89%,目标产物经IR、1H-NMR和13C-NMR验证结构正确。经工艺优化得到最优的反应条件为:投料比n(DANT)∶n(DMBA)为1∶2,DANT为0.01 mol,哌啶用量为2.5mL,25 mL DMSO作溶剂,3 g分子筛作脱水剂,反应温度为130℃,反应时间为11 h。

E-2,5-diacetamido-2＇4＇-dimethoxy-4-nitrostilbene （DADMNS） is synthesised in this study, which is an important intermediate of second order nonlinear optical materials. 2,5-Diacetamido-4-nitrotoluene（DANT） is prepared from 2,5-diaminotoluene via acetylation and nitration. 2,4-Dimethoxybenzaldehyde （ DMBA ） is obtained from 1,3-dimethoxybenzene by Vilsmeier-Haack reaction in the presence of DMF and POC13. With piperdine as catalyst and molecular sieve as dehydrating agent, DANT undergoes a condensation with DMBA in DMF to give the target product DADMNS. The yield and the purity are 73.20% and 98. 89% , respectively. The chemical structure of the target product is confirmed by IR,^1H-NMR,and ^13C-NMR. The optimal reaction parameters are shown as follows： 1：2 of the ratio of DANT to DMBA,0.01 tool of DANT,2. 5 mL of piperidine,25 mL of DMSO,3.0 g of molecular sieve, 130℃ of reaction temperature and 1 hour of reaction time.