Maag Henning, Lemcke Daniel J, Wahl Johannes M
Department Chemie, Johannes Gutenberg-Universität, Duesbergweg 10-14, 55128 Mainz, Germany.
Beilstein J Org Chem. 2024 Jul 19;20:1671-1676. doi: 10.3762/bjoc.20.148. eCollection 2024.
α-Aminoacetophenones are identified as promising building blocks for the synthesis of highly substituted dioxolanes. The presented strategy is founded on the build and release of molecular strain and achieves a formal transposition of a methyl group. During light irradiation, 3-phenylazetidinols are forged as reaction intermediates, which readily undergo ring opening upon the addition of electron-deficient ketones or boronic acids. Key to the successful development of this two-step process is the identification of a benzhydryl-protecting group, which orchestrates the photochemical Norrish-Yang cyclization and facilitates the subsequent ring opening.
α-氨基苯乙酮被认为是合成高度取代二氧戊环的有前景的结构单元。所提出的策略基于分子张力的构建与释放，并实现了甲基的形式上的迁移。在光照过程中，3-苯基氮杂环丁醇作为反应中间体生成，其在加入缺电子酮或硼酸后容易发生开环反应。这一两步过程成功开发的关键在于确定一种二苯甲基保护基，它能协调光化学Norrish-Yang环化反应并促进随后的开环反应。
