Easy direct stereo- and regioselective formation of β-hydroxy nitriles by reaction of 1,2-epoxides with potassium cyanide in the presence of metal salts
A simple efficient, anti stereoselective, and highly regioselectivemethod for the synthesis of β-hydroxy nitriles by the direct opening of 1,2-epoxides with KCN in acetonitrile, in the presence of metal salts, is described. This new method appears to be competitive with the other methods previously reported.
Enabling Deoxygenative C(sp<sup>2</sup>)-C(sp<sup>3</sup>) Cross-Coupling for Parallel Medicinal Chemistry
作者:Wei Liu、James Mulhearn、Bo Hao、Santiago Cañellas、Stefaan Last、José Enrique Gómez、Alexander Jones、Alexander De Vera、Kiran Kumar、Raquel Rodríguez、Lars Van Eynde、Iulia I. Strambeanu、Scott E. Wolkenberg
DOI:10.1021/acsmedchemlett.3c00118
日期:2023.6.8
development of an automated deoxygenative C(sp2)-C(sp3) coupling of aryl bromide with alcohols to enable parallel medicinal chemistry. Alcohols are among the most diverse and abundant building blocks, but their usage as alkyl precursors has been limited. Although metallaphotoredox deoxygenative coupling is becoming a promising strategy to form C(sp2)-C(sp3) bond, the reaction setup limits its widespread
A very simple, safe and powerful method for the in situ generation of formaldehyde at low temperature in anhydrous conditions is described. This new tool avoids the use of gaseous formaldehyde and is suitable for basic carbon nucleophiles which cannot be generated in aqueous reaction media. Various substrates, including organolithium reagents and enolates, underwent smooth hydroxymethylation showing the versatility of this process. A Wittig reaction was also carried out in high yield.
Highly regioselective and stereospecific functionalization of 1,2-propanediol with trimethyl(X)silanes employing the 1,3,2.lambda.5-dioxaphospholane methodology
作者:Isabel Mathieu-Pelta、Slayton A. Evans
DOI:10.1021/jo00038a032
日期:1992.6
The regioselective ring opening of (S)-4-methyl-2,2,2-triphenyl-1,3,2-lambda-5-dioxaphospholane (2) [prepared from the bis(transoxyphosphoranylation) of (S)-1,2-propanediol (1) with diethoxytriphenylphosphorane (DTPP)] was initiated with several trimethylsilyl reagents (Me3SiX: X = PhS, I, Br, Cl, CN, and N3) to afford the regioisomeric (silyloxy)phosphonium salts. A stereospecific extrusion of triphenylphosphine oxide from these oxyphosphonium salts gave predominantly the thermodynamically less stable C-2-X-substituted derivatives with nearly complete inversion of stereochemistry at the C-2 stereogenic center (i.e., X = PhS).