(B2(Pin)2) to approach functionalized dibenzo[b,f][1,4]oxazepine derivatives is developed. The chiral products are obtained in up to 81% yield, >20:1 dr, and 98% ee when either a chiral diphosphine ligand or a chiral ferrocenyl‐based P,N‐ligand is used. Furthermore, the reaction exhibits reversed diastereoselectivities when the chiral diphosphine ligand and the chiral P,N‐ligand are used respectively.
The first organocatalytic asymmetric aza‐Henry reaction of unactivated seven‐membered cyclicimines, dibenzo[b,f][1,4]oxazepines, with nitroalkanes has been achieved. In the presence of 10 mol‐% quinine‐derived thiourea, a range of chiral 11‐(nitromethyl)‐10,11‐dihydrodibenzo[b,f][1,4]oxazepine derivatives were produced in good to excellent yields (up to 97 %) and enantioselectivities (up to 98 % ee)
Preparation of the eight monohydroxydibenz[b,f][1,4]oxazepin-11(10H)-ones
作者:Keith Brewster、Raymond J. Clarke、John M. Harrison、Thomas D. Inch、David Utley
DOI:10.1039/p19760001286
日期:——
The eight possible isomeric monohydroxydibenz[b,f][1,4]oxazepin-11(10H)-ones have been prepared and their mass spectra determined. With the exception of the 7-hydroxy-derivative the fragmentation patterns of the isomers were similar, although the relative line intensities allowed distinctions between the isomers to be made. The syntheses of several irritant monomethoxydibenz[b,f][1,4]oxazepines are
Continuous-flow synthesis of alkyl zinc sulfinates for the direct photofunctionalization of heterocycles
作者:José Luis Nova-Fernández、Montaña J. García、Leonardo Mollari、Gustavo Pascual-Coca、Silvia Cabrera、José Alemán
DOI:10.1039/d2cc01065h
日期:——
A sustainable strategy for the alkylation of heterocycles is presented. The protocol relies on the in situ generation and further in-line use of alkylzinc sulfinates through a continuous-flow system. The environmentally friendly character of the protocol is assured by the use of a green solvent mixture, the presence of a metal free oxidant and low waste generation.
Efficient Construction of Tetracyclic 1,2,4‐Triazoline‐Fused Dibenzo[
<i>b,f</i>
][1,4]oxazepines through KI/TBHP‐Mediated [3+2] Annulation between DBO‐Imines and
<i>N</i>
‐Tosylhydrazones
straightforward protocol for 1,2,4-triazoline-fused dibenzo[b,f][1,4]oxazepines is effectively established throughKI/TBHP-promoted [3+2] annulationbetweendibenzo[b,f][1,4]oxazepine-imines and N-tosylhydrazones under mild conditions. The produced 1,2,4-triazoline-fused DBOs could be easily converted into biologically interesting 1,2,4-triazolo-fused DBOs with excellent yields