Benzylation via Tandem Grignard reaction —iodotrimethylsilane (TMSI) mediated reduction
作者:Eric J. Stoner、Darlene A. Cothron、Mary K. Balmer、Brian A. Roden
DOI:10.1016/0040-4020(95)00659-v
日期:1995.10
initial formation of biarylmethanols via reaction of aryl Grignards with carbonyl compounds followed by a subsequent reduction with iodotrimethylsilane (TMSI). A number of improvements over existing literature procedures are reported as well as previously unobserved dimenzations. Studies reveal that as few as 3 equiv of TMSI will give complete reduction in most cases where either of the substituents are not
Structure–Odor Correlations in Homologous Series of Mercapto Furans and Mercapto Thiophenes Synthesized by Changing the Structural Motifs of the Key Coffee Odorant Furan-2-ylmethanethiol
作者:Sebastian Schoenauer、Peter Schieberle
DOI:10.1021/acs.jafc.8b00857
日期:2018.4.25
seeds. Its unique coffee-like odor quality elicited at very low concentrations, and the fact that only a very few compounds showing a similar structure have previously been described in foods make 1 a suitable candidate for structure–odor activity studies. To gain insight into the structural features needed to evoke a coffee-like odor at low concentrations, 46 heterocyclic mercaptans and thio ethers
It was found that the Claisenrearrangement of the lithium enolate of 1-(2-thienyl)alkyl alkanoate in refluxing THF resulted in the formation of 2-(3-thienyl)alkanoic acid (2). Similarly, when the lithium enolate of 4-(2-thienyl)-4-butanolide was stirred at room temperature in the presence of hexamethylphosphoric triamide, 5,6-dihydro-4H-cyclopenta[b]thiophene-4-carboxylic acid was obtained. Further
from readily-available aryl–alkyl ketones (or alcohols) and different organic azides. Moreover, the reaction used environmentallyfriendlydimethylcarbonate (DMC) as the solvent and air as the oxidant, and H2O was the only by-product, so it provides a green and practical synthetic method for 1,2,3-triazoles.
propan-2-ol. In the presence of potassium hydroxide, the enantioselective reduction of heteroaromatic ketones proceeded smoothly to give chiral alcohols with excellent enantiomeric excess (up to 97% ee) under mild conditions without reduction of the heterocycle. asymmetric - transfer hydrogenation - catalysis - heteroaromatic ketones - heteroaromatic alcohols