Catalysis for Total Synthesis: A Personal Account

Abstract

Divining rod: Natural product synthesis often serves as a divining rod in our search for new and useful catalytic reactivity. This personal account—written in honor of the Max-Planck-Institut für Kohlenforschung on the occasion of its 100th anniversary—summarizes the major lines of research pursued in the author's laboratory, which show how total synthesis and research into basic organometallic chemistry cross-fertilize each other

Total Synthesis of an Exceptional Brominated 4‐Pyrone Derivative of Algal Origin: An Exercise in Gold Catalysis and Alkyne Metathesis

“…From a somewhat larger perspective, this study therefore also helps illustrate the tremendous opportunities that π‐acid catalysis provides for heterocyclic chemistry and natural product synthesis 35. Together with the selective triple‐bond metathesis event as the other key step en route to 1 , it adds a new entry into a now rapidly growing list of examples featuring the strategic advantages of contemporary (catalytic) alkyne chemistry, to which our group is strongly committed 36…”

Expedient Iron‐Catalyzed C−H Allylation/Alkylation by Triazole Assistance with Ample Scope

“…[3,4] Very recently,c onsiderable progress has been made with inexpensive iron complexes to establish novel C À Cf orming processes. [5] Ap articularly powerful approach involves the use of abidentate directing group developed by Daugulis and co-workers. [6] This directing group derived from 8-aminoquinoline (8-AQ) enables ortho-selective C À Hallylation and alkylation reactions,a sw ere devised by Nakamura and coworkers,w ith important contributions by Cook and coworkers.…”

“…[8a,c] Within our program on sustainable CÀHf unctionalization, we have now devised au nified strategy for ironcatalyzed C À Ha llylation/alkylation through triazole assistance.Notable features of our approach include 1) the use of inexpensive iron compounds for challenging CÀHa ctivation reactions,2)aversatile catalyst that enabled aplethora of C À Ha llylation and alkylation reactions of arenes and alkenes, and 3) anovel protocol for the removal of the TAMauxiliary under exceedingly mild reaction conditions. [9] Thei ron-catalyzed C À Ha llylation with substrate 2a proceeded most efficiently with catalysts derived from FeCl 3 or Fe(acac) 3 and the ligand dppe (Table 1; entries [1][2][3][4][5]. [9] Thei ron-catalyzed C À Ha llylation with substrate 2a proceeded most efficiently with catalysts derived from FeCl 3 or Fe(acac) 3 and the ligand dppe (Table 1; entries [1][2][3][4][5].…”

Formation of Ruthenium Carbenes by gem‐Hydrogen Transfer to Internal Alkynes: Implications for Alkyne trans‐Hydrogenation

“…The unorthodox stereochemical course may arise from the intervention of ruthenacyclopropenes (η 2 ‐vinyl complexes)12 as suggested by an in‐depth computational study for the hydrosilylation manifold 13. Although it seems reasonable to assume that the other transformations mentioned above follow similar pathways,14 secured information is largely missing, and alternative mechanisms cannot be ruled out. Specifically, scenarios involving more than one metal center have been proposed in early studies 15.…”