Laboratoire de Chimie Moléculaire, UMR 9168 , Ecole Polytechnique, CNRS , 91128 Palaiseau Cedex , France.
Laboratoire de Synthèse Organique, UMR 7652 , Ecole Polytechnique, ENSTA ParisTech, CNRS , 91128 Palaiseau Cedex , France.
Org Lett. 2018 Apr 20;20(8):2265-2268. doi: 10.1021/acs.orglett.8b00617. Epub 2018 Mar 28.
Oxyallyl cations are prepared in situ from readily available α-tosyloxy ketones and act as transient electrophilic partners in (3 + 3) cycloaddition with nitrones. Under mild conditions, this method provides a chemoselective and diastereoselective route to polysubstituted 1,2-oxazinanes. A stepwise process is proposed to rationalize the diastereoselectivity of this transformation.
氧杂烯丙基阳离子可由易得的α-对甲苯磺酰氧基酮原位制备,并在与硝酮的(3+3)环加成反应中充当瞬态亲电试剂。在温和条件下,该方法为多取代 1,2-噁嗪烷提供了一种化学选择性和立体选择性的合成途径。提出了一个逐步过程来合理化这种转化的立体选择性。