Base-Mediated Meerwein–Ponndorf–Verley Reduction of Aromatic and Heterocyclic Ketones

Abstract

An experimental protocol to achieve the Meerwein−Ponndorf−Verley (MPV) reduction of ketones under mildly basic conditions is reported. The transformation is tolerant of a range of ketone substrates, including O-and S-containing heterocycles, is scalable, and shows potential to be used as a platform to access enantioenriched products. These studies provide a general method for achieving the reduction of ketones under mildly basic conditions and offer an alternative protocol to more well-known Al-based MPV reduction conditions.

Reductive Arylation of Amides via a Nickel‐Catalyzed Suzuki–Miyaura‐Coupling and Transfer‐Hydrogenation Cascade

“…[27] By shifting to the use of i-PrOH as an additive while using toluene as solvent, we obtained the desired product 4 in as lightly improved yield of 32 %, with 18 %o fketone 3 remaining (entry 4). Given our labsrecent success in using 1-4-(dimethylamino)phenyl)-1-ethanol (DMPE, 7)i nb asecatalyzed MPV reductions, [28] we also tested this benzylic alcohol in our system. [29] By simply replacing i-PrOH with 7, alcohol 4 was obtained in 51 %y ield (entry 5).…”

Reductive Arylation of Amides via a Nickel‐Catalyzed Suzuki–Miyaura‐Coupling and Transfer‐Hydrogenation Cascade

“…By shifting to the use of i ‐PrOH as an additive while using toluene as solvent, we obtained the desired product 4 in a slightly improved yield of 32 %, with 18 % of ketone 3 remaining (entry 4). Given our lab's recent success in using 1–4‐(dimethylamino)phenyl)‐1‐ethanol (DMPE, 7 ) in base‐catalyzed MPV reductions, [28] we also tested this benzylic alcohol in our system [29] . By simply replacing i ‐PrOH with 7 , alcohol 4 was obtained in 51 % yield (entry 5).…”

Recent Advances in Nonprecious Metal Catalysis

“…In this case, only the initial coupling is catalyzed by the nickel-NHC complex. The subsequent reduction is the result of a base-mediated Meerwein–Ponndorf–Verley reduction with 4-(dimethylamino)­phenyl)-1-ethanol (DMPE) . The reaction occurs at high temperature and requires a large excess of both the boronate ester nucleophile (4.0 equiv) and reductant (2.5 equiv).…”