26771-69-7Relevant articles and documents
Tandem Acid/Pd-Catalyzed Reductive Rearrangement of Glycol Derivatives
Ciszek, Benjamin,Fleischer, Ivana,Kathe, Prasad,Schmidt, Tanno A.
supporting information, p. 3641 - 3646 (2020/03/25)
Herein, we describe the acid/Pd-tandem-catalyzed transformation of glycol derivatives into terminal formic esters. Mechanistic investigations show that the substrate undergoes rearrangement to an aldehyde under [1,2] hydrogen migration and cleavage of an oxygen-based leaving group. The leaving group is trapped as its formic ester, and the aldehyde is reduced and subsequently esterified to a formate. Whereas the rearrangement to the aldehyde is catalyzed by sulfonic acids, the reduction step requires a unique catalyst system comprising a PdII or Pd0 precursor in loadings as low as 0.75 mol % and α,α′-bis(di-tert-butylphosphino)-o-xylene as ligand. The reduction step makes use of formic acid as an easy-to-handle transfer reductant. The substrate scope of the transformation encompasses both aromatic and aliphatic substrates and a variety of leaving groups.
Experimental study on the reaction pathway of α-haloacetophenones with NaOMe: Examination of bifurcation mechanism
Tagawa, Kohei,Sasagawa, Keita,Wakisaka, Ken,Monjiyama, Shunsuke,Katayama, Mika,Yamataka, Hiroshi
supporting information, p. 119 - 126 (2014/02/14)
The reaction of PhCOCH2Br and NaOMe in MeOH gave PhCOCH 2OH as the major product and PhCOCH2OMe as the minor product. Substituent effects on the reactivity and product selectivity revealed that an electron-withdrawing substituent on the phenyl ring enhanced the overall reactivity and gave more alcohol than ether. It was indicated that the alcohol was formed via carbonyl addition-epoxidation, whereas the ether was formed by direct substitution. Substituent effects on the reaction rates, as well as the effects of NaOMe concentration on the rate and product ratio for both reactions of PhCOCH2Br and PhCOCH2CI are in line with the mechanism that the alcohol and ether products were formed via two independent and concurrent routes, carbonyl addition and a-carbon attack, respectively, and thus the reaction mechanism could be different from the bifurcation mechanism previously predicted for the reaction of PhCOCH2Br by a simulation study in the gas phase.
Piperazine-Based CCR5 Antagonists as HIV-1 Inhibitors. IV. Discovery of 1-[(4,6-Dimethyl-5-pyrimidinyl) carbonyl]-4-[4-{2-methoxy-1(R)-4-(trifluoromethyl)-phenyl}ethyl-3(S) -methyl-1-piperazinyl]-4-methylpiperidine (Sch-417690/Sch-D), a Potent, Highly Sel
Tagat, Jayaram R.,McCombie, Stuart W.,Nazareno, Dennis,Labroli, Marc A.,Xiao, Yushi,Steensma, Ruo W.,Strizki, Julie M.,Baroudy, Bahige M.,Cox, Kathleen,Lachowicz, Jean,Varty, Geoffrey,Watkins, Robert
, p. 2405 - 2408 (2007/10/03)
The nature and the size of the benzylic substituent are shown to be the key to controlling receptor selectivity (CCR5 vs M1, M2) and potency in the title compounds. Optimization of the lead benzylic methyl compound 3 led to the methoxymethyl analogue 30,
