Iridium‐Catalyzed Enantioselective Hydrogenation of Indole and Benzofuran Derivatives
作者:Yao Ge、Zheng Wang、Zhaobin Han、Kuiling Ding
DOI:10.1002/chem.202002532
日期:2020.12
Enantioselectivehydrogenation of a broad spectrum of N‐, O‐, and S‐containing aromatic benzoheterocycles or nonaromatic unsaturated heterocycles has been realized by using an Ir/SpinPHOX (SpinPHOX=spiro[4,4]‐1,6‐nonadiene‐based phosphine‐oxazoline) complex as the catalyst, affording an array of the corresponding chiral benzoheterocycles (30 examples) with excellent enantioselectivities (>99 % ee in
The first enantioselective synthesis of isoflavonoids: (R)- and (S)-isoflavans
作者:Marietjie Versteeg、Barend C. B. Bezuidenhoudt、Daneel Ferreira、Kenneth J. Swart
DOI:10.1039/c39950001317
日期:——
α-Benzylation of (+)- and (–)-N-phenylacetyl imidazolidinones with 2-O-methoxymethylbenzyl bromide, followed by reductive removal of the chiral auxiliary and cyclization, leads to isoflavans in excellent enantiomeric excess and yield.
Asymmetricaddition of arylboronicacids to 2H-chromenes proceeded in the presence of a hydroxorhodium/chiral diene catalyst to give 3-arylchromanes in high yields with high enantioselectivity. The reaction involves 1,4-Rh shift before protonation to release the addition product and to regenerate the hydroxorhodium species.