Gold complexes carbene

Gold carbene complexes preparation, oxidation, and ligand displacement. Journal of Organometallic Chemistry,... 

A dinuclear gold-carbene complex is obtained when the reaction is carried out with the diamine HNCH3C6H12NHCH3 (Figure 7.13) [11]. This dinuclear compound... 

Gold(I)-catalysed cycloisomerizations of enynes (38) afford gold-carbene complexes (39) that have been trapped in an intramolecular fashion yielding highly strained tetracycles (40).38... 

Figure 26 Isomers of gold carbene complexes obtained from coordinated isonitriles.

Four main methods have been established for the preparation of gold carbene complexes and a large number of compounds are known. 

P. Chen Gas-phase synthesis and reactivity of a gold carbene complex a gold benzylidene complex ion was observed, corresponding to the presumed reactive intermediates of a gold-catalyzed cyclopropanation reaction. [220]... 

Gold complexes can also be utilized as catalysts for the synthesis of pyrroles from 1,5-diynes. 2,5-Dimethylpyrrole is synthesized from the reaction of hexa-l,5-diyne and ammonia in the presence of a gold-carbene complex, Au-I [13] ... 

A relay catalytic hydroamination/redox reaction for the synthesis of cyclic aminals 83 from tertiary amine-substituted 3-en-l-yne derivatives 81 and various aniline derivatives 82 was recently developed by Gong and coworkers (Scheme 12.40) [43]. The gold carbene complex [(IPrlAuNTfj] and TfOH were found to be optimal cocatalysts for this cascade reaction. In their preliminary studies, the authors found that this reaction could be carried out in a highly enantioselective manner, despite that 2 equiv. of an expensive chiral phosphoric acid are required. Interestingly, the diastereoselectivity for a particular substrate appears to be independent of the catalyst or ee. This suggests that the enantioselectivity may result from the ring-closure step, rather than the hydride shift step. 

The C—H insertion of a gold carbene complex provided the formation of tetracyclic cyclopropanes 320 (Scheme 1.156) [226]. 

Scheme 7 Synthesis of gold-carbene complexes 16 from imidazolium derived ionic liquid 15...

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