Revisiting Nickel-Catalyzed Carbonylations: (Unexpected) Observation of Substrate-Dependent Mechanistic Differences

The (hydroxy)­carbonylation
of tertiary aliphatic alcohols and their
corresponding olefins with a Ni-based catalyst system is investigated.
This study builds on a previous mechanistic investigation into the
Ni-catalyzed carbonylation of alcohols. The findings differed from
what could be explained with the previously reported mechanisms, prompting
this in-depth mechanistic study. Combined experimental and quantum
chemical efforts are crucial for the rationalization of the observed
reactivities and ultimately help reveal another isobutene-based catalytic
pathway, accessible with these substrates. This study further expands
the knowledge about Ni-catalyzed carbonylation reactions, which have
been known for more than 70 years but were scarcely studied in detail
from a mechanistic point of view.

本研究针对镍基催化剂体系（Ni-based catalyst system）下，脂肪族叔醇（tertiary aliphatic alcohols）及其对应烯烃（olefins）的（羟基）羰基化（hydroxycarbonylation）反应展开了系统探究。本研究基于此前针对醇类镍催化羰基化反应的机理研究工作开展，所得实验结果与已有报道的反应机理所能阐释的现象存在偏差，这一差异推动了本次深入的机理研究。结合实验与量子化学（quantum chemical）的研究手段，对所观测到的反应活性进行合理化阐释具有关键意义，并最终助力揭示一条可适用于该类底物（substrates）的、基于异丁烯（isobutene）的全新催化反应路径。本研究进一步拓展了学界对镍催化羰基化反应的认知——这类反应虽已被发现七十余年，但从机理层面展开的系统性详细研究却极为匮乏。