presence of Mn26 indicating that this catalyst serves as a template for the condensation step [52, 53].
A different type of olefination reaction was independently reported by the groups
of Kempe [54] and Maji [55] within a very short period of time (Scheme 33). In
contrast to the seminal work of Kempe, Maji and coworkers employed [Mn(CO) 5 Br]
and L12 as precursors rather than a well-defined complex. Mechanistic studies
revealed that this manganese catalyst is able to perform AAD of the primary alcohol
but also increased the rate of the condensation step indicating that the manganese
complex serves as platform for C-C bond formation.
Scheme 31 Oxidative coupling of alcohols catalyzed by Mn1
Scheme 32 α-Olefination of nitriles via ADC employing Mn26
Scheme 33 Olefination of various heteroarenes catalyzed by Mn(I) complexes
The Role of Metal-Ligand Cooperation in Manganese(I)-Catalyzed. . .
247
A different type of olefination reaction was independently reported by the groups
of Kempe [54] and Maji [55] within a very short period of time (Scheme 33). In
contrast to the seminal work of Kempe, Maji and coworkers employed [Mn(CO) 5 Br]
and L12 as precursors rather than a well-defined complex. Mechanistic studies
revealed that this manganese catalyst is able to perform AAD of the primary alcohol
but also increased the rate of the condensation step indicating that the manganese
complex serves as platform for C-C bond formation.
Scheme 31 Oxidative coupling of alcohols catalyzed by Mn1
Scheme 32 α-Olefination of nitriles via ADC employing Mn26
Scheme 33 Olefination of various heteroarenes catalyzed by Mn(I) complexes
The Role of Metal-Ligand Cooperation in Manganese(I)-Catalyzed. . .
247