描述了一种温和且操作简单的铜催化乙烯基有氧氧化 β,γ-和 α,β-不饱和酯。该方法具有收率好、底物范围广、化学选择性和区域选择性好、官能团耐受性好等特点。该方法还能够氧化β,γ-和α,β-不饱和醛、酮、酰胺、腈和砜。此外,本催化体系适用于双乙烯基和三乙烯基氧化。发现四甲基胍 (TMG) 作为碱的作用至关重要,但我们也推测它可以作为三氟甲磺酸铜 (II) 的配体来生产活性铜 (II) 催化剂。进行的机械实验表明,通过烯丙基铜 (II) 物质存在一个合理的反应途径。最后,
Enantioselective organocatalytic formal allylation of α-branched aldehydes
作者:Eduardo Rodrigo、Sara Morales、Sara Duce、José Luis García Ruano、M. Belén Cid
DOI:10.1039/c1cc14909a
日期:——
Heteroarylvinyl sulfone 1 has been successfully used as a new sulfonyl Michael acceptor in aminocatalytic reactions with branched aldehydes. Subsequent one-pot JuliaâKocienski olefination allows the challenging preparation of enantiomerically pure α-allylated aldehydes bearing C-α quaternary carbons.
Disclosed are novel aromatic enol ethers. The aromatic enol ethers exhibit low volatile organic content and are reactive film-hardening compounds. The aromatic enol ethers are useful in a variety of chemical applications. The aromatic enol ethers can be used in applications as plasticizers, diluents, wetting agents, coalescing aids and as intermediates in chemical processes. The aromatic enol ethers also have utility as film-hardening additives for coating formulations.
The Proline-Catalyzed Asymmetric Amination of Branched Aldehydes
作者:Thomas Baumann、Henning Vogt、Stefan Bräse
DOI:10.1002/ejoc.200600654
日期:2007.1
An efficient access to configurationally stable α,α-disubstituted α-amino aldehydes, oxazolidinones, and α-amino acids has been presented. Starting from simple and easily available racemic aldehydes, the α-aminated products were obtained using azodicarboxylates as the nitrogen source in up to 86 % ee and moderate to excellent yield. These products could further be converted both into the corresponding
is driven by a novel activation strategy and features a unique Pd(I)-Pd(I) mechanism, involving an iodide-assisted binuclear step to release the product. This method enables β-selective hydroformylation of a large range of alkenes and alkynes, including sensitive starting materials. Its utility is demonstrated in the synthesis of antiobesity drug Rimonabant and anti-HIV agent PNU-32945. In a broader