Reductive Cleavage of Amides to Alcohols and Amines Catalyzed by Well‐Defined Bimetallic Molybdenum Complexes

Abstract

Triple bonds do it! The molybdenum‐catalyzed CN bond cleavage of organic amides with hydrosilanes to produce alcohols and amines has been investigated. This work complements previously established protocols that lead to the cleavage of the CO bond. Modified triply bonded dimolybdenum(III) alkoxides have been found to be crucial for tuning the selectivity to CN bond cleavage (see figure).

Combined KOH/BEt3 Catalyst for Selective Deaminative Hydroboration of Aromatic Carboxamides for Construction of Luminophores

“…Complementary to the direct hydrogenolysis of amide derivatives is the use of hydrosilanes as hydrogen donors, providing a promising alternative method because of its safety and operational simplicity (Scheme b). The elegant works of Enthaler and Fernández-Alvarez using Mo-catalyzed or Ir-catalyzed hydrosilylation of amides allow access to the hydrolyzed products. However, current hydrosilylation approaches frequently suffer from using complex metal catalysts, noble/air-sensitive silanes (Ph 2 SiH 2 and HSiMe 2 Ph), and non-ideal selectivity.…”

Highly Chemoselective Reduction of Amides (Primary, Secondary, Tertiary) to Alcohols using SmI2/Amine/H2O under Mild Conditions

“…Additionally, Enthaler and co-workers reported a bimetallic Mo complex for the catalytic hydrosilylation of N -aryl tertiary amides with good C–N scission chemoselectivity. 9 However, these reactions suffer from limited substrate scope and typically require highly specialized pressure tube and glovebox equipment, which limits their laboratory application. Moreover, primary and secondary amides are difficult substrates because of the presence of free NH bonds.…”

“…tertiary amides) to alcohols using existing hydride-mediated 3,4 and hydrogenation 6−9 methodologies (Table 2). Amides with increasing steric demand at the α carbon were suitable substrates for the reduction (entries 1–5), including a very hindered N , N -diethyl adamantyl amide (entry 5).…”

Nickel complexes with a O,N,O′-ligand and a phosphane co-ligand – Monometallic versus bimetallic complexes

“…On the one hand, an O,O 0 -coordination after deprotonation was observed, while the addition of base revealed a second deprotonation and a O,N-coordination [5,6]. A similar O,O 0 -motif was observed for coordination to molybdenum, resulting in attractive precatalysts for the reduction of organic amides to amines [7]. In case of copper a N,O 0 -coordination was detected with triphenylphosphane as co-ligand and application in copper-catalyzed amination of CH bond was realized [8].…”