Enantioselective synthesis of the farnesyltransferase inhibitor, A-345665.0
摘要:
The stereoselective synthesis of A-345665.0 1, a novel farnesyl transferase inhibitor, is described. The key step involves a stereoselective addition of an imidazolyl Grignard reagent to aldehyde 8 in the presence of an external chiral auxiliary. Crystallization of the product as the dimeric zinc complex 12 facilitates the isolation of product in > 98:2 er. The biaryl linkage is formed by the use of a Suzuki coupling, employing boronic acid 4 prepared by the directed ortho-lithiation of benzonitrile 6. The overall yield for the six step sequence is 21%. (c) 2006 Elsevier Ltd. All rights reserved.
Direct anodic (thio)acetalization of aldehydes with alcohols (thiols) under neutral conditions, and computational insight into the electrochemical formation of the acetals
A versatile protocol for the production of acetals/thioacetals by means of direct electrochemical oxidation is developed here under neutral conditions, providing (thio)acetals with good functional group tolerance and a wide scope for both aldehydes and (thio)alcohols. DFT calculations reveal that direct electron transfer from the anode plays a key role in carbonyl activation during this acid free acetalization
to prepare nitriles from aldehydesusing hexamethyldisilazane (HMDS) as the nitrogen source has been developed. The reactions were performed with 2,2,6,6‐tetramethylpiperidine l‐oxyl (TEMPO) as the catalyst, NaNO2 or TBN as the co‐catalyst, and molecular oxygen as the terminal oxidant under mild conditions. A variety of aromatic, heteroaromatic, aliphatic and allylic aldehydes could be converted into
A simple and efficient method for the directsynthesis of nitriles from aldehydes using ammonium acetate as the nitrogen source has been developed. The reactions were performed with iodine as the catalyst and tert-butyl hydroperoxide (TBHP) as the oxidant under mild conditions. A variety of aromatic, heteroaromatic, aliphatic and allylic aldehydes could be converted into their corresponding nitriles
This is the first report of a simple and general method for acetalization of aldehydes via an α-chymotrypsin-induced reaction under mild conditions. A broad range of aromatic and heteroaromatic aldehydes have been acetalized under neutral conditions in good yields using a catalytic amount of chymotrypsin.
Visible-Light-Induced Acetalization of Aldehydes with Alcohols
作者:Hong Yi、Linbin Niu、Shengchun Wang、Tianyi Liu、Atul K. Singh、Aiwen Lei
DOI:10.1021/acs.orglett.6b03403
日期:2017.1.6
have achieved a simple and general method for acetalization of aldehydes by means of a photochemical reaction under low-energy visible light irradiation. A broad range of aromatic, heteroaromatic, and aliphatic aldehydes have been protected under neutral conditions in good to excellent yields using a catalytic amount of Eosin Y as the photocatalyst. Our visible light mediated acetalization strategies are