Methods for synthesizing isohexide-3,6-dicarbaldehydes and/or isohexide-3,6-dimethanamines from the dehydration products of sugar alcohols (isohexides) and corresponding derivatives are described. The methods involve initially converting the -OH moieties of an isohexide into triflates using triflic anhydride at low temperatures, followed by a carbon-centered nitrile-for-triflate substitution, forming crystalline isohexide-3,6-dinitriles. The isohexide-3,6-dinitriles are then reacted with a reducing agent, such as a metal hydride, in an anhydrous organic solvent at very low temperatures to generate isohexide-3,6-dicarbaldehydes. In a subsequent reductive animation, the isohexide-3,6-dicarbaldehydes are first converted into corresponding diimines, which can be isolated, or then reduced to isohexide-3,6-dimethanamines.
本文介绍了从糖醇(异己糖)的脱
水产物及其衍
生物中合成异己糖-3,6-二醛和/或异己糖-3,6-
二甲胺的方法。该方法首先使用
三氟乙酸酐在低温下将异己糖的-OH官能团转化为
三氟甲烷磺酰基,然后进行碳中心的腈-
三氟甲烷磺酰基取代反应,形成晶体异己糖-3,6-二腈。然后在无
水有机溶剂中,使用
金属
氢化物等还原剂在极低温度下将异己糖-3,6-二腈还原生成异己糖-3,6-二醛。在随后的还原
氨基化反应中,异己糖-3,6-二醛首先被转化为相应的二
亚胺,可以被分离出来,或者被进一步还原为异己糖-3,6-
二甲胺。