Catalytic asymmetric synthesis of chiral phosphanes

Chiral phosphanes, important ligands for metal-catalyzed asymmetric syntheses, are often prepared with compounds from the chiral pool, by using stoichiometric chiral auxiliaries, or by resolution. In some cases, this class of valuable compounds can be prepared more efficiently by catalytic asymmetric synthesis. This Concepts article presents an overview of these synthetic methods, including recent advances in catalysis by metal complexes, biocatalysis, organocatalysis, and ligand-accelerated catalysis.     

双中心协同催化作用在不对称合成中的应用

介绍了双中心协同催化作用的概念以及A型和B型两类催化剂。综述了A型催化 剂在不对称硝基－类羟醛反应、迈克尔加成反应、亚胺和醛的氢膦酰化反应、曼尼 希反应、不对称醛酮羟醛反应以及环氧开环反应中的应用；同时简要介绍了B型催 化剂在不对称合成中的应用。     

手性氨基醇在不对称催化中的应用及新进展

综述了手性氨基醇作为配体或催化剂在不对称合成中的应用及最新进展。     

Exploiting threefold symmetry in asymmetric catalysis: the case of tris(oxazolinyl)ethanes ("trisox")

Rotational molecular symmetry, modularity and other aspects of ligand design have played a role in the development of a new class of stereodirecting ligands. The use of highly symmetrical, stereodirecting ligands may reduce the number of transition states and diastereomeric reaction intermediates and, in favourable cases, this degeneration of alternative reaction pathways may lead to high stereoselectivity in catalytic reactions and greatly simplifies the analysis of such transformations. In this concept article, we describe the way in which these considerations have played a role in the development of a new class of stereodirecting ligands. Tris(oxazolinyl)ethanes ("trisox") have proved to be versatile ligand systems for the development of enantioselective catalysts of the d- and f-block metals employed in a wide range of catalytic conversions. These include Lewis acid catalysed transesterifications, C-C and C-N coupling reactions, the catalytic polymerisation of alpha-olefins as well as Pd-catalysed allylic alkylations. An overview of the current state of this field is given and the potential for further development will be highlighted.     

Asymmetric catalysis with helical polymers

Inspired by nature, the use of helical biopolymer catalysts has emerged over the last years as a new approach to asymmetric catalysis. In this Concept article the various approaches and designs and their application in asymmetric catalysis will be discussed.     

Recent applications of chiral ferrocene ligands in asymmetric catalysis

Despite the impressive progress achieved in asymmetric catalysis during the last decade, an increasing number of new catalysts, ligands, and applications are reported every year to satisfy the need to embrace a wider range of reactions and to improve the efficiency of existing processes. Because of their availability, unique stereochemical aspects, and wide variety of coordination modes and possibilities for the fine-tuning of the steric and electronic properties, ferrocene-based ligands constitute one of the most versatile ligand architectures in the current scenario of asymmetric catalysis. Over the last few years ferrocene catalysts have been successfully applied in an amazing variety of enantioselective processes. This Review documents these recent advances, with special emphasis on the most innovative asymmetric processes and the development of novel, efficient types of ferrocene ligands.     

"Designer acids": combined acid catalysis for asymmetric synthesis

Lewis and Brønsted acids can be utilized as more‐effective tools for chemical reactions by sophisticated engineering (“designer acids”). The ultimate goal of such “designer acids” is to form a combination of acids with higher reactivity, selectivity, and versatility than the individual acid catalysts. One possible way to take advantage of such abilities may be to apply a “combined acids system” to the catalyst design. The concept of combined acids, which can be classified into Brønsted acid assisted Lewis acid (BLA), Lewis acid assisted Lewis acid (LLA), Lewis acid assisted Brønsted acid (LBA), and Brønsted acid assisted Brønsted acid (BBA), can be a particularly useful tool for the design of asymmetric catalysis, because combining such acids will bring out their inherent reactivity by associative interaction, and also provide more‐organized structures that allow an effective asymmetric environment.     

Simple, but challenging: recent developments in the asymmetric synthesis of spiroketals

Impressive and elegant approaches to the enantioselective synthesis of spiroketals starting from achiral substrates have been described recently. These strategies based on transition-metal catalysis and organocatalysis hold great potential for further applications.     

Aerobic asymmetric oxygenation catalysis: a well forgotten… future?

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手性炔丙醇的不对称催化合成研究进展

手性炔丙醇是一种重要中间体化合物,作为合成多种光学活性化合物的重要合成前体受到学者们广泛关注。目前通过酮的不对称催化反应合成手性炔丙醇的研究开发具有极大发展前景,因此本文围绕酮类化合物的不对称催化反应来进行综述,结合相关反应最新研究进展,全面总结并分类了不对称催化还原、催化不对称加成等反应类型,介绍了合成不同结构手性炔丙醇的新思路,并对酮的不对称催化反应在未来能成为工业化重要生产途径作出展望。