2-(N,N-diethylcarbamoyloxy)allylsilane. Dual reactivity with α,α′-acetone dianion and allene 1,2-dipole equivalency
摘要:
The title compound displays the dual role of an alpha,alpha'-acetone dianion 4 and an allene 1,2-dipole 5 equivalent allowing the preparation of versatile synthetic intermediates 10a-c and 11a-d (Tables 1 and 2).
[EN] METHODS FOR INDUCING BIOORTHOGONAL REACTIVITY<br/>[FR] PROCÉDÉS POUR INDUIRE UNE RÉACTIVITÉ BIO-ORTHOGONALE
申请人:FOX JOSEPH
公开号:WO2017106427A1
公开(公告)日:2017-06-22
A method for catalytically converting a dihydrotetrazine 1 into a tetrazine 2, wherein one R group on the dihydrotetrazine 1 is a substituted or unsubstituted aryi, heteroaryl, alkyl, alkenyl, alkynyl, carbonyl, or heteroatom-containing group, and the other R group is selected from the group consisting of H and substituted or unsubstituted aryl, heteroaryl, alkyl, alkenyl, alkynyl, carbonyl,-or heteroatom-containing groups; 1, 2 wherein the method comprises oxidizing dihydrotetrazine 1 in a reaction medium in the presence of a catalyst and a stoichiometric oxidant.
Highly-functionalised difluorinated (hydroxymethyl)conduritol analogues via the Diels–Alder reactions of a difluorinated dienophile
作者:Andrea Arany、Patrick J. Crowley、John Fawcett、Michael B. Hursthouse、Benson M. Kariuki、Mark E. Light、Andrew C. Moralee、Jonathan M. Percy、Vittoria Salafia
DOI:10.1039/b314314g
日期:——
A difluorodienophile, synthesised using a Stille coupling reaction underwent tin(IV)-catalysed cycloaddition with three furans to afford oxa[2.2.1]bicycloheptenes in good yield. Reduction of ester and carbamate carbonyl groups and diol protection as the acetonide set the stage for palladium-catalysed hydrostannylation in two cases. Treatment of the stannanes with methyllithium triggered ring-opening to afford highly-functionalised difluorinated cyclohexenols which could be deprotected to afford (hydroxymethyl)conduritol analogues.
A mild, efficient, and general Negishi cross coupling protocol, 4 + 5 → 6 is reported; the hydrolysis of products 6 to acetophenones demonstrates the anionicFriedel-Craftsequivalency of the overall synthetic operation.
Vinyl carbamate compounds are prepared by reacting appropriate secondary amines with carbon dioxide and acetylenically unsaturated compounds in the presence of a compound of a metal from the platinum group, in particular a ruthenium compound, with either one of the two process steps (a) and (b) or, preferably, both being carried out: (a) the acetylene compound is reinjected during the reaction; (b) the reaction is carried out in the presence of a tertiary amine.
Enantioselective Rh-Catalyzed Hydrogenation of Enol Acetates and Enol Carbamates with Monodentate Phosphoramidites
作者:Lavinia Panella、Ben L. Feringa、Johannes G. de Vries、Adriaan J. Minnaard
DOI:10.1021/ol051559c
日期:2005.9.1
[reaction: see text] Monodentate phosphoramidites, in particular PipPhos and its octahydro analogue, are excellent ligands for the rhodium-catalyzedasymmetrichydrogenation of aromatic enol acetates, enol carbamates, and 2-dienol carbamates up to 98% ee. These latter substrates were hydrogenated selectively to the carbamates of the allyl alcohol.