Search

Abstract: Re‐investigation of the l‐proline catalyzed double aldol cascade dimerization of succinaldehyde for the synthesis of a key bicyclic enal intermediate, pertinent in the field of stereoselective prostaglandin synthesis, is reported. The yield of this process has been more than doubled, from 14 % to a 29 % isolated yield on a multi‐gram scale (32 % NMR yield), through conducting a detailed study of the reaction solvent, temperature, and concentration, as well as a catalyst screen. The synthetic utility of this enal intermediate has been further demonstrated through the total synthesis of Δ12‐prostaglandin J3, a compound with known anti‐leukemic properties. [ABSTRACT FROM AUTHOR]

Abstract: Re‐investigation of the l‐proline catalyzed double aldol cascade dimerization of succinaldehyde for the synthesis of a key bicyclic enal intermediate, pertinent in the field of stereoselective prostaglandin synthesis, is reported. The yield of this process has been more than doubled, from 14 % to a 29 % isolated yield on a multi‐gram scale (32 % NMR yield), through conducting a detailed study of the reaction solvent, temperature, and concentration, as well as a catalyst screen. The synthetic utility of this enal intermediate has been further demonstrated through the total synthesis of Δ12‐prostaglandin J3, a compound with known anti‐leukemic properties. [ABSTRACT FROM AUTHOR]

A scalable, metal-free dearomatization of substituted pyridines is described, and depending on the substituents′ position structurally diverse azacycles are formed selectively. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Boron-Catalyzed Silylative Reduction of Quinolines: Selective sp³ C-Si Bond Formation" by N. Gandhamsetty and others, published in the periodical "Journal of the American Chemical Society" in 2015.

(-)-Finerenone is a nonsteroidal mineralocorticoid receptor antagonist currently in phase III clinical trials for the treatment of chronic kidney disease in type 2 diabetes. It contains an unusual dihydronaphthyridine core. We report a 6-step synthesis of (-)-finerenone, which features an enantioselective partial transfer hydrogenation of a naphthyridine using a chiral phosphoric acid catalyst with a Hantzsch ester. The process is complicated by the fact that the naphthyridine exists as a mixture of two atropisomers that react at different rates and with different selectivities. The intrinsic kinetic resolution was converted into a kinetic dynamic resolution at elevated temperature, which enabled us to obtain (-)-finerenone in both high yield and high enantioselectivity. DFT calculations have revealed the origin of selectivity., (© 2020 Wiley-VCH GmbH.)

Re-investigation of the l-proline catalyzed double aldol cascade dimerization of succinaldehyde for the synthesis of a key bicyclic enal intermediate, pertinent in the field of stereoselective prostaglandin synthesis, is reported. The yield of this process has been more than doubled, from 14 % to a 29 % isolated yield on a multi-gram scale (32 % NMR yield), through conducting a detailed study of the reaction solvent, temperature, and concentration, as well as a catalyst screen. The synthetic utility of this enal intermediate has been further demonstrated through the total synthesis of Δ 12 -prostaglandin J 3 , a compound with known anti-leukemic properties., (© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

The B(C6F5)3-catalyzed silylative reduction of conjugated nitriles has been developed to afford synthetically valuable β-silyl amines. The reaction is chemoselective and proceeds under mild conditions. Mechanistic elucidation indicates that it proceeds by rapid double hydrosilylation of the conjugated nitrile to an enamine intermediate which is subsequently reduced to the β-silyl amine, thus forming a new C(sp(3))-Si bond. Based on this mechanistic understanding, a preparative route to enamines was also established using bulky silanes., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)