oxadiazepines via 1,5-hydride shift/cyclization of pyrrolidine- or tetrahydroisoquinoline-containing nitrones has been developed. With 1,3-dipole nitrones serving as the hydride acceptors, this transformation was promoted by a Lewis acid, providing access to structurally diverse oxadiazepines in good yields. A one-pot process for in situ nitrone formation, a 1,5-hydride shift, and ring cyclization was also
Catalyst-free construction of spiro [benzoquinolizidine-chromanones] <i>via</i> a tandem condensation/1,5-hydride transfer/cyclization process
作者:Siyuan Liu、Hang Wang、Baomin Wang
DOI:10.1039/d0ob01887b
日期:——
A highly efficient and quite mild protocol to achieve spiro [benzoquinoline-chromanones] through a catalyst-free condensation/[1,5]-hydride shift/6-endo cyclization sequence was developed.
Diastereoselective Spirocyclization via Intramolecular C(
<i>sp</i>
<sup>3</sup>
)−H Bond Functionalization Triggered by Sequential [1,5]‐Hydride Shift/Cyclization Process: Approach to Spiro‐tetrahydroquinolines
作者:Arup Bhowmik、Sumit Das、Writhabrata Sarkar、K. M. Saidalavi、Aniket Mishra、Anupama Roy、Indubhusan Deb
DOI:10.1002/adsc.202001011
日期:2021.2.2
functionalization triggered by sequential [1,5]‐ hydrideshift /cyclization sequence using ortho amino benzaldehydes and active methylene compounds such as 2‐coumaranone, 4‐hydroxycoumarin, 3‐coumaranone, and 3‐isochromanone. This protocol provides a Lewis acid catalyst‐free straight forward one‐pot reaction in cases of 2‐coumaranone and 4‐hydroxycoumarin, Lewis acid‐catalyzed stepwise reaction for 3‐coumaranone