Complex-Induced Proximity Effect in the Regioselective Lithiation of Pyridine Derivatives
作者:Jaspreet S. Dhau、Amritpal Singh、Yoganjaneyulu Kasetti、P. V. Bharatam
DOI:10.1002/ejoc.201101592
日期:2012.3
The regioselective ring lithiation of BF3-complexed 3-picoline (1a), 3,4-lutidine (1b), and 3,5-lutidine (1c) was studied. The dilithiation of 1a, 1b, and 1c was also investigated to experimentally explore the relative preference of the sites on the substituted pyridine ring for lithiation. The role of the complex-induced proximity effect (CIPE) for inducing lithiation in these moieties was investigated
Transition-Metal Free Chemoselective Hydroxylation and Hydroxylation–Deuteration of Heterobenzylic Methylenes
作者:Yonghai Liu、Yang Yu、Chengyu Sun、Yiwei Fu、Zhiguo Mang、Lei Shi、Hao Li
DOI:10.1021/acs.orglett.0c03108
日期:2020.10.16
We developed an approach for direct selective hydroxylation of heterobenzylic methylenes to secondary alcohols avoiding overoxidation to ketones by using a KOBu-t/DMSO/air system. Most reactions could reach completion in several minutes to give hydroxylated products in 41-76% yields. Using DMSO-d6, this protocol resulted in difunctionalization of heterobenzylic methylenes to afford α-deuterated secondary alcohols (>93% incorporation). By employing this method, active pharmaceutical ingredients carbinoxamine and doxylamine were synthesized in two steps in moderate yields.
KURBATOVA, A. S.;KURBATOV, YU. V.;NIYAZOVA, D. A., ZH. ORGAN. XIMII, 26,(1990) N, S. 649-652
作者:KURBATOVA, A. S.、KURBATOV, YU. V.、NIYAZOVA, D. A.
DOI:——
日期:——
Catalysis of linear alkene metathesis by Grubbs-type ruthenium alkylidene complexes containing hemilabile α,α-diphenyl-(monosubstituted-pyridin-2-yl)methanolato ligands
作者:Tegene T Tole、Johan H L Jordaan、Hermanus C M Vosloo
DOI:10.3762/bjoc.15.19
日期:——
Four new Grubbs-type precatalysts [RuCl(H2IMes)(O^N)(=CHPh)], where [O^N = α,α-diphenyl-(3-methylpyridin-2-yl)methanolato, α,α-diphenyl-(4-methylpyridin-2-yl)methanolato, α,α-diphenyl-(5-methylpyridin-2-yl)methanolato and α,α-diphenyl-(3-methoxypyridin-2-yl)methanolato] were synthesized and tested for their activity, stability and selectivity in the 1-octene metathesis reaction. Overall the precatalysts