[EN] COMPOSITIONS AND METHODS FOR THE PREPARATION OF 4-OXY-2-CYCLOHEXENONE AND 6-OXY-2-CYCLOHEXENONE COMPOUNDS [FR] COMPOSITIONS ET PROCÉDÉS POUR LA PRÉPARATION DE COMPOSÉS 4-OXY-2-CYCLOHEXÉNONE ET 6-OXY-2-CYCLOHEXÉNONE
A Stereoselective Approach to Functionalized Cyclohexenones
作者:Anne C. Meister、Paul F. Sauter、Stefan Bräse
DOI:10.1002/ejoc.201300752
日期:2013.11
A catalytic enantioselective approach to 4-hydroxy-6-methylcyclohex-2-enones is presented herein. The stereogenic information is generated through a copper-catalyzed 1,4-addition to p-benzoquinone monoketal using a chiral, BINOL-based (BINOL = 1,1′-bi-2-naphthol) phosphane ligand, according to the procedure of Feringa et al. A CBS (Corey–Bakshi–Shibata) reduction of the 1,4-adducts gave the four possible
A catalytic route to acyclic chiral building blocks: Applications of the catalytic asymmetric conjugate addition of organozinc reagents to cyclic enones
作者:Richard B. C. Jagt、Rosalinde Imbos、Robert Naasz、Adriaan J. Minnaard、Ben L. Feringa
DOI:10.1560/nhk0-c8je-27g9-nub3
日期:2001.12
asymmetric conjugateaddition a number of chiral cyclic enones are available with high ee. Here we report the sequential conjugateaddition to these enones as a route towards multisubstituted chiral cyclic ketones. A subsequent Baeyer—Villiger oxidation followed by ring-opening results in various linear synthons containing multiple stereocenters. This procedure represents a short, catalytic, and highly enantioselective
The first totalsynthesis of (+)-pedrolide, a tigliane-derived diterpenoid featuring an unprecedented 5–5–6–6–3 carbon skeleton, is reported. Key to the approach is the construction of the bicyclo[2.2.1]heptane core via an intramolecular cyclopentadiene-Diels–Alder cycloaddition. To this end, a norbornadiene serves as an effective surrogate for cyclopentadiene, which is unmasked under mild conditions
Enantioselective Synthesis of Biphenols from 1,4-Diketones by Traceless Central-to-Axial Chirality Exchange
作者:Fenghai Guo、Leah C. Konkol、Regan J. Thomson
DOI:10.1021/ja108717r
日期:2011.1.12
A method for the enantioselective synthesis of biphenols from readily prepared 1,4-diketones is reported. Key to the success of this method is the highly selective transfer of central to axial chirality during a double aromatization event triggered by BF3 center dot OEt2. On the basis of X-ray crystallographic data, a stereochemical model for this chirality exchange process is put forth.
Highly Enantioselective Catalytic Conjugate Additions to Cyclohexadienones
作者:Rosalinde Imbos、Mirjan H. G. Brilman、Mauro Pineschi、Ben L. Feringa
DOI:10.1021/ol990707u
日期:1999.8.1
Enantioselective copper phosphoramidite-catalyzed conjugate addition of dialkylzinc reagents (R2Zn) to several 4,4-disubstituted cyctohexadienones was achieved with dr's up to 99/1 and ee's up to 99%.