PMID: 11916413Mar 28, 2002Paper

Highly anti-selective asymmetric aldol reactions using chiral zirconium catalysts. Improvement of activities, structure of the novel zirconium complexes, and effect of a small amount of water for the preparation of the catalysts

Journal of the American Chemical Society
Yasuhiro YamashitaShū Kobayashi

Abstract

Catalytic asymmetric aldol reactions of silyl enol ethers with aldehydes (Mukaiyama aldol reactions) have been performed using novel chiral zirconium catalysts. The reactions proceeded in high yields under mild conditions, and anti-adducts were obtained in high diastereo- and enantioselectivities. The catalysts were first prepared from zirconium(IV) tert-butoxide (Zr(O(t)Bu)(4)), (R)-3,3'-diiodo-1,1'-binaphthalene-2,2'-diol ((R)-3,3'-I(2)BINOL), a primary alcohol, and a small amount of water. It was revealed that the primary alcohol played an important role in completing the catalytic cycle and that a small amount of water was essential for obtaining high selectivities. Moreover, activities of the chiral zirconium catalysts were enhanced by using new ligands, (R)-3,3'-I(2)-6,6'-X(2)BINOL (X = Br, I, C(2)F(5)), and it has been shown that even aldol reactions of less reactive substrates proceeded smoothly using the novel zirconium catalysts. Finally, NMR studies of these catalysts were performed, which suggested that the catalyst would form a dimeric structure and that the water affected the catalyst formation.

Citations

Mar 14, 2009·Organic Letters·Michael T Crimmins, Anne-Marie R Dechert
Sep 30, 2006·Chemical Communications : Chem Comm·Darryl J MorrisonRobert McDonald
Apr 7, 2004·Proceedings of the National Academy of Sciences of the United States of America·Shu KobayashiYasuhiro Yamashita
Feb 18, 2016·Chemical Reviews·Liang HongRui Wang
Sep 25, 2017·Chemistry : a European Journal·Sun Min KimJung Woon Yang
May 31, 2018·Chemical Society Reviews·Yasuhiro YamashitaShū Kobayashi
Mar 17, 2010·Chemistry : a European Journal·Marcus FringsCarsten Bolm
Apr 28, 2007·Organic & Biomolecular Chemistry·Kazutaka SekiShū Kobayashi
May 16, 2019·Chemical Communications : Chem Comm·Jindong LiZhiyong Wang
Oct 9, 2013·Chemistry, an Asian Journal·Taku KitanosonoShū Kobayashi
May 28, 2020·Organic & Biomolecular Chemistry·Dian Agung Pangaribowo, Manabu Abe
Feb 10, 2004·Chemical Society Reviews·Claudio PalomoJesús M García
Aug 14, 2003·Chemical Reviews·Yu ChenAndrei K Yudin
Jun 13, 2009·The Journal of Organic Chemistry·Jens BunzenArne Lützen
Sep 27, 2002·Organic Letters·Masaharu UenoShū Kobayashi
Jul 3, 2020·The Journal of Organic Chemistry·Kento YasumotoKeiji Maruoka
Apr 3, 2013·The Journal of Organic Chemistry·Daniel R FandrickChris H Senanayake
Nov 7, 2002·Journal of the American Chemical Society·Scott E DenmarkGregory L Beutner
Nov 15, 2002·Journal of the American Chemical Society·Shū KobayashiJun Kobayashi

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.