Efficient Synthesis of (S)-2-(Cyclopentyloxycarbonyl)-amino-8-nonenoic Acid: Key Building Block for BILN 2061, an HCV NS3 Protease Inhibitor
摘要:
A new procedure for the practical synthesis of (S)-2-(cyclopentyloxycarbonyl)amino-8-nonenoic acid, a key building block for BILN 2061, an HCV NS3 protease inhibitor, has been developed. The key step features a kinetic resolution of racemic 2-acetylamino-8-nonenoic acid with acylase I. In addition, the undesired (R)-2-acetylamino-8-nonenoic acid was recycled after racemization. The procedure was implemented for the production of (S)-2-(cyclopentyloxycarbonyl)amino-8-nonenoic acid on pilot-plant scale.
An Ir(ppy)3-catalyzed vic-diphosphination of styrenes with Me3Si-PPh2 and NFSI proceeds under blue LED irradiation to afford the corresponding bis(diphenylphosphino)ethane derivatives without any formation of hydrophosphination byproducts, which are inevitable and problematic under the previous Cu/NHC catalysis. Additionally, the visible-light-promoted photoredox catalysis enables the diphosphination
Me 3 Si-PPh 2和NFSI对苯乙烯进行Ir(ppy)3催化的维克二磷酸化,在蓝色LED辐射下进行,得到相应的双(二苯基膦基)乙烷衍生物,而没有形成任何磷酸化副产物,这在不可避免的情况下是有问题的先前的Cu / NHC催化。另外,可见光促进的光氧化还原催化能够使相对具有挑战性的脂族烯烃和β-取代的苯乙烯进行二磷酸化。
Catalytic Enantioselective Allylic Amination of Unactivated Terminal Olefins via an Ene Reaction/[2,3]-Rearrangement
作者:Hongli Bao、Uttam K. Tambar
DOI:10.1021/ja307851b
日期:2012.11.14
The enantioselective allylic amination of unactivated terminal olefins represents a direct and attractive strategy for the synthesis of enantioenriched amines. We have developed the first use of a nitrogen-containing reagent and a chiral palladium catalyst to convert unfunctionalized olefins into enantioenriched allylic amines via an ene reaction/[2,3]-rearrangement.
The intramolecular acylation of some hex-, hept-, and oct-enoic acids
作者:M. F. Ansell、J. C. Emmett、R. V. Coombs
DOI:10.1039/j39680000217
日期:——
acids. Intramolecular acylation of these acids in the presence of trifluoroacetic anhydride is shown to be dependent on the structure and stereochemistry of the acids. The formation of cyclohept-2-enone from hept-6-enoic acid is reported. Concentrated sulphuric acid in acetic anhydride is shown to convert hex- and hept-5-enoic acid into phenyl and o-tolyl acetate, respectively. Some improved syntheses
Allylic Functionalization of Unactivated Olefins with Grignard Reagents
作者:Hongli Bao、Liela Bayeh、Uttam K. Tambar
DOI:10.1002/anie.201309134
日期:2014.2.3
the functionalization of unactivated olefins with carbonnucleophiles have provided moreefficient and practical approaches to convert inexpensive starting materials into valuable products. Recent examples have been reported with stabilized carbonnucleophiles, tethered carbonnucleophiles, diazoesters, and trifluoromethane donors. A general method for functionalizing olefins with aromatic, aliphatic
Catalytic Allylation of Aldehydes Using Unactivated Alkenes
作者:Shun Tanabe、Harunobu Mitsunuma、Motomu Kanai
DOI:10.1021/jacs.0c04735
日期:2020.7.15
and a chromium complex catalyst, enabling catalytic allylation of aldehydes with simplealkenes, including feedstock lower alkenes. The reaction proceeded under visible-light irradiation at room temperature and with high functional group tolerance. The reaction was extended to an asymmetric variant by employing a chiral chromium complex catalyst.