Manganese coupling reaction

Mn. Manganese is also effective for mediating aqueous carbonyl ally-lations and pinacol-coupling reactions. Manganese offers a higher reactivity and complete chemoselectivity toward allylation of aromatic aldehydes.178... 

For pinacol coupling reactions with a catalytic amount of Cp2TiCl2 and reductants such as zinc and manganese, high, V7-selectivities are observed frequently. The mechanism for the stereoselectivities has been explained by a... 

The unique versatility of ruthenium as an oxidation catalyst continues to provide a stimulus for research on a variety of oxidative transformations. Its juxtaposition in the periodic table and close similarity to the biological redox elements, iron and manganese, coupled with the accessibility of various high-valent oxo species by reaction of lower-valent complexes with dioxygen make ruthenium an ideal candidate for suprabiotic catalysis. 

Most of the polymer-forming oxidative coupling reactions known are catalytic processes by virtue of the reoxidation of the transition metal ion with an oxidant, preferably oxygen (air). Cuprio-cuprous complexes serve most prominently as catalysts (I, 2, 3, 9, 10, 11, 12, 17, 18, 19, 20, 30) manganese (24) and cobalt (6) complexes have also been used. 

Cobalt-, Manganese- and Iron-catalyzed Cross-coupling Reactions 9.4.2.1 Carbonylations and acylations... 

Chromium. In 1998, Boland reported a chromium(n)-catalyzed pinacol coupling reaction of aromatic aldehydes and ketones (Eq. 3.28) [46-48J aliphatic aldehydes are inert to these conditions. The turnover step relies upon a combination of manganese and Me3SiCl to regenerate CrX2 from an intermediate chromi-um(III) species (Fig. 3-3). 

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