Sequential Protocol for C(sp3)–H Carboxylation with CO2: Transition-Metal-Catalyzed Benzylic C–H Silylation and Fluoride-Mediated Carboxylation
摘要:
One of the most challenging transformations in current organic chemistry is the catalytic carboxylation of a C(sp(3))-H bond using CO2 gas, an inexpensive and ubiquitous Cl source. A sequential protocol for C(sp(3))-H carboxylation by employing a nitrogen-directed, metal-assisted, C-H activation/catalytic silylation reaction in conjunction with fluoride-mediated carboxylation with CO2 was established. The carboxylation proceeded only at the benzylic C(sp(3))-Si bond, not at the aromatic C(sp(2))-Si, which is advantageous for further manipulations of the products.
Kumada-Corriu Cross-Couplings with 2-Pyridyl Grignard Reagents
作者:Lutz Ackermann、Harish K. Potukuchi、Anant R. Kapdi、Carola Schulzke
DOI:10.1002/chem.201000032
日期:2010.3.15
SPOs meet the challenge: A palladium complex derived from air‐ and moisture‐stable secondaryphosphineoxide (SPO) (1‐Ad)2P(O)H enables general cross‐couplingreactions of challenging electron‐deficient 2‐pyridyl Grignard reagents with ample scope (see scheme).