腈类化合物的新法合成

New method for synthesis of nitriles

本文报道腈类化合物的一种新合成方法。以各种醛(2a~2q)为原料,分别与盐酸羟胺反应得到一系列醛肟中间体(3a~3q),然后在叠氮磷酸二苯酯(DPPA)和1,8-二氮杂二环十一碳-7-烯(DBU)作用下,得到一系列腈类化合物(1a~1q)。中间体及产物结构均经过~1H NMR和ESI-MS表征。其中,中间体3i、3l及产物1q结构进一步通过X-单晶衍射确证。并以2-硝基苯甲醛肟(3a)和2-硝基苯腈(1a)的合成为模型,考察反应的主要影响因素。确定产物腈的合成条件为:DPPA用量为n(DPPA)∶n(化合物3a)=1.1∶1,DBU用量为n(DBU)∶n(3a)=1.2∶1,在25℃反应30 min,产物2-硝基苯腈(1a)收率为68.5%。该合成方法工艺简单、反应时间短、产物收率高、底物适用性广、原料廉价易得,为腈类化合物的合成提供了一种高效的新方法。

A new synthetic method of nitriles was reported.A series of aldoxime intermediates(3a~3q)were synthesized from aldehydes(2a~2q)with hydroxylamine hydrochloride,then a series of nitriles(1a~1q)were synthesized by the reaction of aldoxime with DPPA and DBU.The structure of intermediates and products were characterized by 1H NMR and ESI-MS.The structure of 3i,3l and 1q were further confirmed by X-ray single crystal diffraction.Also,the effect of reaction conditions on the yield of 2-nitrobenzonitrile(1a)was investigated as model reaction.The synthetic conditions of the product nitrile were determined as follows:The amount of DPPA:n(DPPA)∶n(3a)=1.1∶1,the dosage of DBU:n(DBU)∶n(3a)=1.2∶1,the yield of 2-nitrobenzonitrile(1a)was 68.5%at 25℃ for 30 min.The method had the advantages of simple process,short reaction time,high yield,wide tolerance of substrates and low cost of raw materials.It provided a new and efficient method for the synthesis of nitriles.