functionalized dihydro-[1,3]oxazino[4,3-a] isoindole and tetrahydroisoquinoline skeletons has been developed through the addition-cyclization process of ynamides 8 with N-acyliminium ions generated from N,O-acetals 6,7. The reactions were conducted under the catalysis of Cu(OTf)2, and a number of functionalized dihydro-[1,3]oxazino[4,3-a] isoindoles 9a-9y and tetrahydroisoquinolines 10a-10g, 11a-11p
Stereoselective Synthesis of Pyrido- and Pyrrolo[1,2-<i>c</i>][1,3]oxazin-1-ones via a Nucleophilic Addition–Cyclization Process of <i>N</i>,<i>O</i>-Acetal with Ynamides
作者:Pan Han、Zhuo-Ya Mao、Chang-Mei Si、Zhu Zhou、Bang-Guo Wei、Guo-Qiang Lin
DOI:10.1021/acs.joc.8b02795
日期:2019.1.18
An efficient asymmetric approach to access functionalized pyrido- and pyrrolo[1,2-c][1,3]oxazin-1-ones has been developed through a nucleophilic addition–cyclization process of N,O-acetal with ynamides. A number of substituted ynamides 8a–8o and 3-silyloxypyrrolidine or piperidine N,O-acetals 6a, 7 were amenable to this transformation, and the desired products 9a–9o, 10a–10m were obtained with excellent
Asymmetric Hydrative Aldol Reaction (HAR) via Vinyl‐Gold Promoted Intermolecular Ynamide Addition to Aldehydes
作者:Teng Yuan、Kelton Radefeld、Chuan Shan、Carter Wegner、Erin Nichols、Xiaohan Ye、Qi Tang、Lukasz Wojtas、Xiaodong Shi
DOI:10.1002/anie.202305810
日期:2023.8
application of Fe(acac)3 as a cocatalyst prevents vinyl gold protodeauration, allowing for its nucleophilic addition to aldehydes. Hence, the intermolecular vinyl gold-promoted asymmetric hydrative aldolreaction (HAR) of ynamides and aldehydes was shown possible and is herein presented. The reaction leads to β-hydroxy amides with high yields (up to 95 %) and stereoselectivity (up to >20 : 1 d.r, 99 % ee) under