CC BY-NC-ND 4.0 · Synthesis 2021; 53(21): 3991-4003
DOI: 10.1055/a-1535-3215
short review

Assembling Complex Structures through Cascade and Cycloaddition Processes via Non-Acceptor Gold or Rhodium Carbenes

Helena Armengol-Relats
a   Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
b   Departament de Química Orgànica i Analítica, Universitat Rovira i Virgili, C/ Marcel·lí Domingo s/n, 43007 Tarragona, Spain
,
Mauro Mato
a   Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
b   Departament de Química Orgànica i Analítica, Universitat Rovira i Virgili, C/ Marcel·lí Domingo s/n, 43007 Tarragona, Spain
,
Imma Escofet
a   Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
b   Departament de Química Orgànica i Analítica, Universitat Rovira i Virgili, C/ Marcel·lí Domingo s/n, 43007 Tarragona, Spain
,
a   Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
b   Departament de Química Orgànica i Analítica, Universitat Rovira i Virgili, C/ Marcel·lí Domingo s/n, 43007 Tarragona, Spain
› Author Affiliations
We thank the Ministerio de Ciencia e Innovación (PID2019-104815GB-I00) (FPI predoctoral fellowship to M.M. and FPU predoctoral fellowship to H.A.-R.), Severo Ochoa Research Excellence Accreditation 2020-2023 (CEX2019-000925-S), the European Research Council (Advanced Grant No. 835080), the Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) (2017 SGR 1257), and the Centres de Recerca de Catalunya (CERCA) Program/Generalitat de Catalunya for financial support.


Abstract

The ability of highly energetic metal–carbene intermediates to engage in complex cascade or formal cycloaddition processes is one of the most powerful tools for building intricate molecular architectures in a straightforward manner. Among this type of organometallic intermediates, non-acceptor metal carbenes are particularly challenging to access and, therefore, have experienced slower development. In this regard, our group has exploited the use of electrophilic gold(I) complexes to selectively activate certain classes of substrates for the generation of this type of intermediate. Thus, very different types of molecules, such as enynes or 7-substituted cycloheptatrienes, lead to the formation of carbenes under gold(I) catalysis. Related rhodium(II) carbenes can also be generated from cycloheptatrienes. In this account, we aim to summarize our efforts towards the in situ generation of such highly versatile organometallic species as well as studies on their reactivity through formal cycloadditions or complex cascade reactions.

1 Introduction

2 Generation of Au(I)-Vinylcarbenes via a Cycloisomerization/1,5-Alkoxy Migration Cascade

2.1 Intramolecular Trapping of Au(I) Vinylcarbenes

2.1.1 Applications in Total Synthesis

2.2 Intermolecular Trapping of Au(I) Vinylcarbenes

2.2.1 Total Synthesis of Schisanwilsonene A

2.2.2 Trapping with Furans, 1,3-Dicarbonyl Compounds and Cyclic Alkenes

2.2.3 Mechanism of the Cycloisomerization/1,5-Migration Sequence and the Role of the OR Migrating Group

2.2.4 (4+3) Cycloadditions from Enynes

3 Formal Cycloadditions of Simple Donor Metal Carbenes

3.1 The Metal-Catalyzed Retro-Buchner Reaction

3.2 Formal Cycloadditions with Non-Acceptor Carbenes via Metal-Catalyzed Aromative Decarbenations

3.2.1 (4+1) Cycloadditions of Au(I) Carbenes

3.2.2 (3+2) Cycloadditions of Au(I) Carbenes

3.2.3 (4+3) Cycloadditions of Rh(II) Carbenes

4 Concluding Remarks



Publication History

Received: 31 May 2021

Accepted after revision: 24 June 2021

Accepted Manuscript online:
24 June 2021

Article published online:
31 August 2021

© 2021. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

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