Dedicated to Prof. Günter Helmchen on the occasion of his 81st birthday
Abstract
Coupling reactions stand amid the most significant reactions in synthetic organic chemistry. Of late, these coupling strategies are being viewed as a versatile synthetic tool for a wide range of organic transformations in many sectors of chemistry, ranging from indispensable synthetic scaffolds and natural products of biological significance to novel organic materials. Further, the use of dual-catalysis in accomplishing various interesting cross-coupling transformations is an emerging field in synthetic organic chemistry, owing to their high catalytic performance rather than the use of a single catalyst. In recent years, synthetic organic chemists have given considerable attention to hetero-dual catalysis; wherein these catalytic systems have been employed for the construction of versatile carbon–carbon [C(sp
3)–C(sp
3), C(sp
3)–C(sp
2), C(sp
2)–C(sp
2)] and carbon–heteroatom (C–N, C–O, C–P, C–S) bonds. Therefore, in this mini-review, we are emphasizing recently developed various cross-coupling reactions catalysed by transition-metal dual-catalysis (i.e., using palladium and copper catalysts, but omitting the reports on photoredox/metal catalysis).
1 Introduction
2 Cu/Pd-Catalysed Bond Formation
2.1 Pd/Cu-Catalysed C(sp
3)–C(sp
2) Bond Formation
2.2 Pd/Cu-Catalysed C(sp
2)–C(sp
2) Bond Formation
2.3 Pd/Cu-Catalysed C(sp)–C(sp
2) Bond Formation
2.4 Pd/Cu-Catalysed C(sp
3)–C(sp
3) Bond Formation
2.5 Pd/Cu-Catalysed C–X (X = B, N, P, S, Si) Bond Formation
3 Conclusion
Key words
dual-metal catalysis - cross-coupling reactions - Kinugasa reaction - palladium catalysis - heterocycles