Syntheses of the principal bread flavor component, 6-acetyl-1,2,3,4-tetrahydropyridine, and acetal protected precursors
作者:Norbert De Kimpe、Christian Stevens
DOI:10.1016/0040-4020(94)01104-8
日期:1995.2
Various synthetic approaches towards the principle bread flavor component, 6-acetyl-1,2,3,4-tetrahydropyridine, and some of its more stable acetal and enol ether derivatives have been developed by elaboration and ring closure of appropriately functionalized imines. The aza-Wittig type cyclization of functionalized δ-azido ketones, carrying an acetal function at the α′-position, proved to be the most
通过对适当官能化的亚胺进行精制和闭环,已经开发出多种用于制备面包风味成分,6-乙酰基-1,2,3,4-四氢吡啶及其一些更稳定的乙缩醛和烯醇醚衍生物的合成方法。功能化的δ-叠氮基酮的aza-Wittig型环化反应是最成功的途径,在α'-位带有乙缩醛功能。导致不稳定的面包风味成分的合成方案包括(1)非对称α-二酮的区域选择性缩醛化和(2)进入稳定的受保护的缩醛衍生物。所需的δ-氯酮的替代物在α'-位带有乙缩醛功能,包括相应的δ-氯-亚胺的选择性水解。此外,已经合成了美拉德风味化合物的一些N-烷基化类似物。乙缩醛保护的2-乙酰基四氢吡啶的替代方法包括δ-氯亚胺的初始叠氮化,在乙缩醛部分存在下亚胺官能团的选择性水解和环状亚胺的分子内氮杂-维蒂希型形成。