Monoaryloxide-pyrrolide

Cross-Alkane Metathesis In a parallel study on cross-alkane metathesis using supported, Ta polyhydrides [34], Schrock and coworkers recently reported the dual-catalytic, homogenous, cross-alkane metathesis of n-octane, and ethylbenzene. The authors [136] employed various W-monoaryloxide pyrrolide complexes in combination with several iridium pincer complexes. For example, employing Ir-2(H2) and W-1 with a ratio of n-octane/ethylbenzene (1 1.33, in v/v) produced the best productivity toward alkylbenzenes, with good selectivity over linear alkanes (Scheme 2.20). 

Alternatively, monoaryloxide-pyrrolide (MAP) complexes of Mo and W have been developed. It was found that the methyUdene species of these complexes were quite stable toward bimolecular decomposition, yet very reactive [20]. As such, MAP catalysts are very efficient in reactions, including the ethenolysis of methyl oleate [21], enantioselective RCM [22], and Z-selective homocouplings and cross metatheses [23, 24]. MAP catalysts are further discussed in detail in Chapters 1, 6, and see Grubbs, Handbook of Metathesis, 2nd Edition, Volume 2, Chapter 7. 

Recent Development of Mo- and W-Alkylidene Monoaryloxide Pyrrolide Complexes for Highly Z-Selective Olefin Metathesis... 

In the past few years the groups of Schrock at MIT and Hoveyda at Boston College introduced a new type of Mo-alkylidene MonoAryloxide Pyrrolide (MAP) complexes as highly reactive and enantioselective olefin metathesis catalysts [56,57]. These stereogenic-at-metal complexes supported by non-chelating ligands turned out to be fascinating catalysts forZ-selective olefin metathesis reactions with the level of Z-selectivities that was completely out of reach before. 

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