Sequential protocol for C(sp3)-H carboxylation with CO2: transition-metal-catalyzed benzylic C-H silylation and fluoride-mediated carboxylation.
One of the most challenging transformations in current organic chemistry is the catalytic carboxylation of a C(sp(3))-H bond using CO(2) gas, an inexpensive and ubiquitous C1 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 CO(2) 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.
Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan. tmita@pharm.hokudai.ac.jp
Tsuyoshi
T
Mita
Kenichi
K
Michigami
Yoshihiro
Y
Sato
D002245:Carbon Dioxide / Q000737:chemistry*; D002264:Carboxylic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D005459:Fluorides / Q000737:chemistry*; D015394:Molecular Structure; D012821:Silanes / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D028561:Transition Elements / Q000737:chemistry*
D002264:Carboxylic Acids; D012821:Silanes; D028561:Transition Elements; D002245:Carbon Dioxide; D005459:Fluorides