A Metal-Free Approach for Brønsted Acid Promoted C–H Alkylation of Heteroarenes with Alkyl Peroxides
作者:Bo Qian、Hongli Bao、Yuehua Zeng、Yajun Li
DOI:10.1055/s-0037-1609965
日期:2018.8
for Minisci C–H alkylation of heteroarenes using alkyl peroxides as the alkylating reagents and internal oxidants simultaneously under promotion of Brønsted acid has been demonstrated. A series of alkyl substituted heteroarenes were readily prepared by the C–H alkylation in moderate to good yields. A possible pathway involving the addition of alkyl radical to heterocycle followed by rearomatization
Long‐ing alkyl chain: The catalytic direct CH alkylation of azoles with unactivatedalkyl bromides and chlorides is described. A palladium catalyst enables the alkylation of oxazoles, whereas a nickel one shows unique activity for thiazole. The catalyses allow a straightforward access to azole motifs bearing long, functional alkyl side chains.
User-Friendly [(Diglyme)NiBr<sub>2</sub>]-Catalyzed Direct Alkylations of Heteroarenes with Unactivated Alkyl Halides through CH Bond Cleavages
作者:Lutz Ackermann、Benudhar Punji、Weifeng Song
DOI:10.1002/adsc.201100487
日期:2011.12
A nitrogen and phosphorus ligand-free catalytic system derived from inexpensive [(diglyme)NiBr2] allowed for efficient direct CH bondalkylations of heteroarenes with unactivated β-hydrogen-containing alkylhalides under basic reaction conditions.
benzothiazole derivatives in high yields was provided via copper catalyzed tandem cyclization with o-haloanilines, elemental sulfur and terminal alkynes as raw materials. In this protocol, C atoms on the CC triplebond were controllably involved in the construction of the benzothiazole framework and multiple carbon–heteroatom bonds through divergent routes.
Ruthenium catalyzed β-selective alkylation of vinylpyridines with aldehydes/ketones <i>via</i> N<sub>2</sub>H<sub>4</sub> mediated deoxygenative couplings
作者:Leiyang Lv、Chao-Jun Li
DOI:10.1039/d0sc06586b
日期:——
aldehyde/ketones via N2H4 mediated deoxygenative couplings. Compared with one-electron umpolung of carbonyls to alcohols, this two-electron umpolung strategy realized reductive deoxygenation targets, which were not only applicable to the regioselective alkylation of a broad range of 2/4-alkene substituted pyridines, but also amenable to challenging 3-vinyl and steric-embedded internal pyridines as well as their