7632-16-8Relevant articles and documents
Pauson-Khand Reactions with Concomitant C?O Bond Cleavage for the Preparation of 5,5- 5,6- and 5,7-Bicyclic Ring Systems
Ma, Ding,Hu, Naifeng,Ao, Junli,Zang, Shaoli,Yu, Guo,Liang, Guangxin
supporting information, p. 1887 - 1891 (2021/02/26)
Pauson-Khand reactions (PKR) with concomitant C?O bond cleavage have been developed for construction of 5,5- 5,6- and 5,7-bicyclic ring systems bearing complex stereochemistry. The chemistry generates intermolecular PKR-type products in an absolute regio- and stereochemical control which is hardly achievable through real intermolecular Pauson-Khand reactions. A mechanism for this Pauson-Khand reaction has been proposed based on deuterium labelling experiments. (Figure presented.).
Chiral Imidazo[1,5- a]pyridine-Oxazolines: A Versatile Family of NHC Ligands for the Highly Enantioselective Hydrosilylation of Ketones
Chinna Ayya Swamy,Varenikov, Andrii,Ruiter, Graham De
supporting information, p. 247 - 257 (2020/02/04)
Herein we report the synthesis and application of a versatile class of N-heterocyclic carbene ligands based on an imidazo[1,5-a]pyridine-3-ylidine backbone that is fused to a chiral oxazoline auxiliary. The key step in the synthesis of these ligands involves the installation of the oxazoline functionality via a microwave-assisted condensation of a cyano-azolium salt with a wide variety of 2-amino alcohols. The resulting chiral bidentate NHC-oxazoline ligands form stable complexes with rhodium(I) that are efficient catalysts for the enantioselective hydrosilylation of structurally diverse ketones. The corresponding secondary alcohols are isolated in good yields (typically >90%) with good to excellent enantioselectivities (80-93% ee). The reported hydrosilylation occurs at ambient temperatures (40 °C), with excellent functional group tolerability. Even ketones bearing heterocyclic substituents (e.g., pyridine or thiophene) or complex organic architectures are hydrosilylated efficiently, which is discussed further in this report.
Chemoselective Luche-Type Reduction of α,β-Unsaturated Ketones by Magnesium Catalysis
Jang, Yoon Kyung,Magre, Marc,Rueping, Magnus
, p. 8349 - 8352 (2019/10/16)
The chemoselective reduction of α,β-unsaturated ketones by use of an economic and readily available Mg catalyst has been developed. Excellent yields for a wide range of ketones have been achieved under mild reaction conditions, short times, and low catalyst loadings (0.2-0.5 mol %).
