Amphoteric α-Boryl Aldehydes

A new class of stable molecules, α-boryl aldehydes, has been prepared from oxiranyl N-methyliminodiacetyl boronates by a 1,2-boryl migration with concomitant epoxide scission. A range of boryl imines, alkenes, alcohols, acids, enol ethers, enamides, and other functionalized boronic acid derivatives that are difficult or impossible to prepare using established protocols can be accessed from α-boryl aldehydes. The chemoselective transformations of these building blocks, including the facile synthesis of functionalized unnatural amino acids from silyloxy and amido vinyl boronates, attest to the potential of α-boryl aldehydes in chemical synthesis.

本研究通过环氧乙基N-甲基亚氨基二乙酸硼酸酯（oxiranyl N-methyliminodiacetyl boronates）的1,2-硼迁移伴随环氧键断裂反应，成功制备了一类新型稳定分子α-硼基醛（α-boryl aldehydes）。
α-硼基醛可用于合成一系列采用现有合成策略难以甚至无法制备的硼基亚胺、烯烃、醇、羧酸、烯醇醚、烯酰胺及其他官能化硼酸衍生物。
此类合成砌块的化学选择性转化反应（例如从硅氧基与酰胺基乙烯基硼酸酯便捷合成官能化非天然氨基酸），证实了α-硼基醛在化学合成领域的应用潜力。