Transition metal-catalyzed carbon–carbon bond activation

Abstract

This tutorial review deals with recent developments in the activation of C-C bonds in organic molecules that have been catalyzed by transition metal complexes. Many chemists have devised a variety of strategies for C-C bond activation and significant progress has been made in this field over the past few decades. However, there remain only a few examples of the catalytic activation of C-C bonds, in spite of the potential use in organic synthesis, and most of the previously published reviews have dwelt mainly on the stoichiometric reactions. Consequently, this review will focus mainly on the catalytic reaction of C-C bond cleavage by homogeneous transition metal catalysts. The contents include cleavage of C-C bonds in strained and unstrained molecules, and cleavage of multiple C-C bonds such as C[triple bond]C triple bonds in alkynes. Multiple bond metathesis and heterogeneous systems are beyond the scope of this review, though they are also fascinating areas of C-C bond activation. In this review, the strategies and tactics for C-C bond activation will be explained.

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).…”

“…Literature scrutiny revealed that significant progress has been made in the field of this research; however, this chemistry has been mainly limited to ringstrained molecules [5][6][7][8][9][10] and specially designed model compounds. 11,12 Herein, we report Sc(OTf) 3 catalysed C-C bond cleavage in ynones that leads to synthesis of ketones that from ynones would have poor atom economy of ketones.…”

“…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. Literature scrutiny revealed that significant progress has been made in the field of this research; however, this chemistry has been mainly limited to ringstrained molecules [5][6][7][8][9][10] and specially designed model compounds.…”

Carbon–Carbon Bond Cleavage by Strongly Electrophilic Boranes

“…While the activation of dihydrogen [1] and subsequently carbon-hydrogen bond activation have been achieved with a large selection of powerful methods, [2][3][4][5] the activation and cleavage of carbon-carbon (C À C) bonds has attracted much less attention. [4][5][6][7] Methodologically it is to be regarded as problematic. There are classical methods known for the selective cleavage of strong unactivated C À C bonds, such as the ozonolysis cycloaddition/cycloreversion sequence [8,9] or the metal-catalyzed olefin metathesis reaction.…”

Rhenium‐katalysierte Aktivierung von C‐H‐ und C‐C‐Bindungen

“…Eine wirklich universelle Methode gibt es bis heute jedoch nicht, woraus sich eine große Herausforderung für die organische Synthese ergibt. [3] Die bisher beschriebenen Strategien zur selektiven Aktivierung der C-C-Einfachbindung beruhen zumeist auf der Verwendung gespannter Ringe, [4] der Wirkung von Chelatbildnern [5] und der Bildung von Metallalkoholaten zur b-Alkyl-Eliminierung. [6] Zwei jüngste Beiträge von Kuninobu und Takai et al über die Rhenium(I)-katalysierte Bildung von C-CBindungen durch direkte C-H-Aktivierung zeigen nun eine gänzlich neue Reaktionsweise auf.…”