Metal Insertion into C−C Bonds in Solution

Abstract

What kind of ligated metal center is necessary for insertion into the "hidden" C-C bond? How can one tune the metal center for C-C bond activation by variation of the steric and electronic properties of ligands? What are the possible mechanisms of C-C bond activation in various reaction systems? A systematic look at the available data on C-C bond activation in solution provides some answers to these questions.

Scandium triflate catalyzed unexpected cleavage of C-C bonds in ynones

“…The use of Ph 3 PAuNTf 2 catalyst also shows somewhat similar results (entry 2). Next, various Lewis acids catalysts such as Cu(OTf) 2 , Zn(OTf) 2 , Yb(OTf) 3, In(OTf) 3 , Sc(OTf) 3 and Bi(OTf) 3 has been investigated (entries [3][4][5][6][7][8] . The best result was obtained with 5 mol% of Sc(OTf) 3 in MeOH that afforded 2a/3a in 87% yield with good regioselectivity (23:1) (entry 7).…”

“…1,2 These types of reactions are often unpredictable and in large part originated with serendipitous observations. 3,4 As a result, the development of reactions involving cleavage of C−C bonds is very difficult to realise and pose serious challenge to synthetic organic chemists.…”

Stereospecific ring expansion from orthocyclophanes with central chirality to metacyclophanes with planar chirality

“…The residue was purified by preparative thin-layer chromatography on silica gel (Hexane:AcOEt ¼ 5:1) to afford (±)-4a (19.9 mg, 0.069 mmol, 69%). 1 Synthesis of ( þ )-4a. The racemic mixture of (±)-5a was separated by chiral preparative HPLC (Daicel CHIRALPAK OZ-H column, hexane:i-PrOH ¼ 90:10).…”

“…Carbon-carbon (C-C) [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] and carbon-hydrogen (C-H) bonds [16][17][18][19][20][21][22][23][24][25] , which are ubiquitous in organic compounds, are intrinsically difficult to activate owing to their thermodynamic stability as well as their kinetic inertness. Selective transformation of such nonpolar s-bonds has provided a challenge that has motivated and inspired chemists to seek ways to activate these bonds over the past two decades.…”

Transition Metal Catalyzed CarbonCarbon Bond Formation: The Key of Homogeneous Catalysis

“…Numerous mechanistic studies have been carried out for understanding reductive elimination from dialkyl or mixed metal complexes of platinum [55][56][57][58][59][60][61][62], palladium [58,[63][64][65][66][67], rhodium [55], ruthenium [60] and iridium [55].…”