Difference in the behavior of methyl (S)-?-bromopropionate in its addition to trimethylvinylsilane depending on the method of initiation
摘要:
The addition of methyl (S)-2-bromopropionate to trimethylvinylsilane initiated by systems based on iron pentacarbonyl affords a racemic adduct and is accompanied by racemization of the unreacted chiral ester. in the presence of benzoyl peroxide, the reaction proceeds similarly, but no racemization of the starring chiral ester occurs.
Organic Dye-Catalyzed Intermolecular Radical Coupling of α-Bromocarbonyls with Olefins: Photocatalytic Synthesis of 1,4-Ketocarbonyls Using Air as an Oxidant
作者:Soumyadeep Roy Chowdhury、Deepak Singh、Injamam Ul Hoque、Soumitra Maity
DOI:10.1021/acs.joc.0c01985
日期:2020.11.6
α-bromocarbonyls where aerial oxygen played a role of an oxidant to install the keto-oxygen functionality. This unique process is compatible with both internal and terminal olefins and tolerates a diverse array of functional groups (ketone, ester, amide, diketones, ketoester, and malonate). This process is mild and environmentally friendly and deals with greener oxidants like oxygen, affording 1,4-ketocarbonyls as
The base-induced asymmetric [2,3] Stevensrearrangement of N-cinnamyl tetraalkylammonium ylides derived from L-alanine amides proceeds via a double axially chiral intermediate to afford the corresponding alpha-substituted alanine derivatives with high enantio- and diastereoselectivities.
Highly Diastereoselective Michael Reactions Using β-Nitrocarbonyl Nucleophiles
作者:Amber A. S. Gietter-Burch、Roxana E. Mitrut、Donald A. Watson
DOI:10.1021/acs.orglett.5b02832
日期:2015.11.6
We have discovered a highly diastereoselective Michael reaction of α-substituted, β-nitrocarbonyl compounds to deliver highly functionalized stereodiads containing fully substituted nitrogen-bearing centers. Good to excellent yields and diastereoselectivities are observed. This transformation is tolerant of various types of carbonyl groups on the nucleophilic partner, as well as a range of unsaturated
[EN] NEW RUTHENIUM COMPLEXES AS CATALYSTS FOR METATHESIS REACTIONS<br/>[FR] NOUVEAUX COMPLEXES DU RUTHÉNIUM COMME CATALYSEURS POUR DES RÉACTIONS DE MÉTATHÈSE
申请人:HOFFMANN LA ROCHE
公开号:WO2009124853A1
公开(公告)日:2009-10-15
The invention relates to novel metathesis catalysts of the formula (I) a process for making the same and their use in metathesis reactions such as ring closing or cross metathesis. The invention further relates to a process for the manufacture of a macrocyclic compound of formula (VII) which have the potential to be useful as HCV protease inhibitors.
Cobalt‐Catalyzed α‐Arylation of Substituted α‐Bromo α‐Fluoro β‐Lactams with Diaryl Zinc Reagents: Generalization to Functionalized Bromo Derivatives
作者:Mélanie M. Lorion、Vanessa Koch、Martin Nieger、Hi‐Yung Chen、Aiwen Lei、Stefan Bräse、Janine Cossy
DOI:10.1002/chem.202001721
日期:2020.10.15
A cobalt‐catalyzed cross‐coupling of α‐bromo α‐fluoro β‐lactams with diarylzinc or diallylzinc reagents is herein disclosed. The protocol proved to be general, chemoselective and operationally simple allowing the C4 functionalization of β‐lactams. The substrate scope was expanded to α‐bromo lactams and amides, α‐bromo lactones and esters as well as N‐ and O‐containing heterocycles.