Oxidative Homologation of Aldehydes to α‐Ketoaldehydes by using Iodoform, o‐Iodoxybenzoic Acid, and Dimethyl Sulf­oxide

Abstract

An efficient three-step synthetic route to α-ketoaldehydes starting from aryl aldehydes is reported. The aldehydes were treated with iPrMgCl and iodoform to obtain β-diiodoalcohols, which were then oxidized with o-iodoxybenzoic acid at room temperature to the corresponding β-diiodoketones.

Searching for Novel Inhibitors of the S. aureus NorA Efflux Pump: Synthesis and Biological Evaluation of the 3‐Phenyl‐1,4‐benzothiazine Analogues

“…Compounds 2 a , 2 b , 2 c – e and 5 a , 5 b , 5 c , 5 d , 5 e were obtained following the procedure depicted in Scheme , by the reaction of benzene‐1,2‐diamine 11 with properly substituted 2‐bromo‐1‐phenylethanones 9 a , 9 b , 9 c , 9 d and 9 e using anhydrous sodium acetate and dry methanol. The spontaneous oxidation of the 2‐phenyl‐3,4‐dihydroquinoxaline intermediates 12 a ‐ e in the corresponding 2‐phenylquinoxaline derivatives gave compounds 5 a , 5 b , 5 c , 5 d , and 5 e . Compounds 2 a , 2 b , and 2 c ‐ e were finally obtained, after reduction in anhydrous condition of 5 a , 5 b , 5 c , 5 d and 5 e using BH 3 ⋅THF in dry THF (Scheme and Table ).…”

“…The spontaneous oxidation of the 2‐phenyl‐3,4‐dihydroquinoxaline intermediates 12 a ‐ e in the corresponding 2‐phenylquinoxaline derivatives gave compounds 5 a , 5 b , 5 c , 5 d , and 5 e . Compounds 2 a , 2 b , and 2 c ‐ e were finally obtained, after reduction in anhydrous condition of 5 a , 5 b , 5 c , 5 d and 5 e using BH 3 ⋅THF in dry THF (Scheme and Table ).…”

“…Synthesis of the 2‐phenyl‐1,2,3,4‐tetrahydroquinoxalines (2 a, 2 b, 2 c–e) and the 2‐phenylquinoxalines (5 a, 5 b, 5 c, 5 d, 5 e). General procedure for the synthesis of compounds 5 a, 5 b, 5 c, 5 d, and 5 e : To a stirring solution of benzene‐1,2‐diamine 7 (1.2 equiv) in dry MeOH (5.00 mL per mmol, anhydrous sodium acetate (1.2 equiv) was added.…”

NIS-mediated ring-closure/opening cascade reactions of allylamides: an expedient route to oxazolines

“…11 Then, the scope of the reaction was investigated. As depicted in Scheme 2, a broad variety of aromatic motifs in R group were well tolerated for this process (4be4f, 52e86% yield).…”

Ein systematischer Vergleich peptidischer Proteasominhibitoren unterstreicht α‐Ketoamid als vielversprechende elektrophile Leitstruktur

“…[10] Dagegen wurde der Aldehyd 1 auf einem zuvor erzeugten Leucinolterminus durch Oxidation mit 2-Iodoxybenzoesäure (IBX) aufgebaut. [11] 2 konnte aus 1 durch eine Grignard-Reaktion mit Iodoform gefolgt von einer Oxidation und Hydrolyse des resultierenden b-Diiodalkohols erhalten werden [12] (siehe die Hintergrundinformationen). Nachdem alle KP-Inhibitoren zur Verfügung standen, wurden IC 50 -Messungen der hauptsächlich betroffenen chymotrypsinartigen Aktivität (ChTL), welche durch das katalytisch aktive Thr1-Nukleophil der b5-Untereinheit vermittelt wird, durchgeführt (Abbildung 1 B).…”