palladium-catalyzed reductive carbonylation with low catalyst loadings (0.5 mol % Pd or below) has been developed. The formylation of aryl and heteroaryl bromides proceeds smoothly in the presence of palladium/di-1-adamantyl-n-butylphosphine at ambient pressure of synthesis gas to afford the corresponding aromatic aldehydes in good yields and excellent selectivity. In addition, vinyl halides react under
Construction of polycyclic structures with vicinal all-carbon quaternary stereocenters <i>via</i> an enantioselective photoenolization/Diels–Alder reaction
present in one molecule, they will dramatically increase its synthetic challenge. A chiral titanium promoted enantioselective photoenolization/Diels–Alder (PEDA) reaction allows largely stereohindered tetra-substituted dienophiles to interact with highly active photoenolized hydroxy-o-quinodimethanes, delivering fused or spiro polycyclic rings bearing vicinal all-carbon quaternary centers in excellent
SELECTIVE HYDROGENATION OF ALDEHYDE WITH RU/BIDENTATE LIGANDS COMPLEXES
申请人:FIRMENICH SA
公开号:US20140243526A1
公开(公告)日:2014-08-28
The present invention relates to processes for the reduction by hydrogenation, using molecular H
2
, of a C
5
-C
20
substrate containing one or two aldehydes functional groups into the corresponding alcohol or diol, characterized in that said process is carried out in the presence of —at least one catalyst or pre-catalyst in the form of a ruthenium complex having a coordination sphere of the N
2
P
2
O
2
, wherein the coordinating atoms N
2
are provided by a first bidentate ligand, the coordinating atoms P
2
are provided by a second bidentate ligand and the coordinating atoms O
2
are provided by two non-linear carboxylate ligands; and —optionally of an acidic additive.
The present invention relates to spiroindolinone derivatives of the formula
and enantiomers and pharmaceutically acceptable salts and esters thereof which have utility as antiproliferative agents, especially, as anticancer agents.
Fifty years after its first discovery by Alan Francis Thomas, we describe a versatile, metal and pressure‐free domino‐Claisen–Cope rearrangement using the readily available α,β‐unsaturated aldehydes 5 or their acetals 5′ and allylic alcohols 6. This transformation provides a convenient access to a large number of radiant citrus and floral rosy odorants. Odor profiles of novel floral rosy and citrus
在艾伦·弗朗西斯·托马斯(Alan Francis Thomas)首次发现五十年之后,我们描述了一种多用途,无金属且无压力的多米诺-克莱森-科普重排方法,它使用易于获得的α,β-不饱和醛5或其缩醛5'和烯丙基醇6进行重排。通过这种转换,可以方便地访问大量的辐射柑橘和花香的玫瑰味气味剂。气味新颖花香红润和柑橘醇的型材13,14,和16进行了研究。化合物14ba具有花香,玫瑰色,天竺葵般的特征,并具有独特的性能和扩散性。复合16ba具有清晰的主要柑橘香气特征,具有干净的绿色葡萄柚/大黄成分。两种香精最近已成功引入Rosyfolia ™(14ba)和Pomelol ™(16ba)香水中。