Asymmetric Friedel-CraftsReactions: Catalytic Enantioselective Addition of Aromatic and HeteroaromaticC-H Bonds to Activated Alkenes, Carbonyl Compounds, andImines
作者:Karl Anker Jørgensen
DOI:10.1055/s-2003-39176
日期:——
aromatic and heteroaromatic C-H bonds to α,β-unsaturated alkenes, carbonylcompounds, and imines are presented. α,β-Unsaturated alkenes, 4-substituted 2-oxo-3-butenoate esters and alkylidene malonates react with indoles, furans and electron-rich aromatic compounds in the presence of chiral bisoxazoline-copper(II) complexes to give the Friedel-Craftsalkylation adduct in moderate to high yields and with
介绍了催化对映选择性加成芳烃和杂芳烃 CH 键与 α,β-不饱和烯烃、羰基化合物和亚胺的发展和范围。α,β-不饱和烯烃、4-取代的 2-氧代-3-丁烯酸酯和亚烷基丙二酸酯与吲哚、呋喃和富电子芳香族化合物在手性双恶唑啉-铜 (II) 配合物存在下反应得到 Friedel-Crafts烷基化加合物,产率中等至高,ee 高达 >99.5%。手性双恶唑啉-铜(II)配合物还可以催化特别是富含电子的芳族化合物与活性羰基化合物如乙醛酸盐和三氟丙酮酸盐的对映选择性加成,从而以良好的收率和对映选择性得到例如光学活性芳族扁桃酸酯。
Enantioselective Nitroaldol Reaction of α-Ketoesters Catalyzed by Cinchona Alkaloids
作者:Hongming Li、Baomin Wang、Li Deng
DOI:10.1021/ja057237l
日期:2006.1.1
The development of highly enantioselective and general catalytic nitroaldol (Henry) reactions with ketones is a challenging yet desirable task in organic synthesis. In this communication, we report an asymmetric nitroaldol reaction with alpha-ketoesters catalyzed by a new C6'-OH cinchonaalkaloid catalyst. This is the first highly efficient organocatalytic asymmetric Henry reaction with ketones. This
5-methoxy-pentono-1,4-lactones from (R)-2-hydroxy-5-methoxy-3-pentenoic acid obtained by bioreduction of the 2-oxo acid
作者:David Bonnaffé、Helmut Simon
DOI:10.1016/s0040-4020(01)81186-8
日期:1992.1
Various 5-methoxy-pentono-1,4-lactones and derivatives thereof were synthesised from propargyl alcohol or its methyl ether. The key step was the enantioselective reduction of 2-oxo-5-alkoxy-3-pentenoic acids by resting cells of Proteus vulgaris. The (R) -2-hydroxy-5-methoxy-3-pentenoic acid (ee. > 96%) was further functionalized via epoxidation, or hydroxylation with osmium tetroxide, or bromine addition