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Rhodium‐Catalyzed Oxidative Alkenylation of Naphthalene: Factors That Influence Reaction at the β‐ versus α‐Position
Author(s) -
Reid Christopher W.,
Baptiste Lauren E.,
Gunnoe T. Brent
Publication year - 2025
Publication title -
chemcatchem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.497
H-Index - 106
eISSN - 1867-3899
pISSN - 1867-3880
DOI - 10.1002/cctc.202500150
Subject(s) - rhodium , naphthalene , catalysis , chemistry , oxidative phosphorylation , oxidative addition , photochemistry , medicinal chemistry , organic chemistry , biochemistry
Abstract The catalyst precursor [(η 2 ‐C 2 H 4 ) 2 Rh(μ‐OAc)] 2 and in situ oxidant Cu(OPiv) 2 (OPiv = t ‐BuCOO – ) convert naphthalene and olefins (i.e., ethylene and propylene) to alkenylnaphthalenes. Under all reaction conditions tested, the functionalization is selective for the β‐position of naphthalene with the highest observed β:α ratio >20:1. The β‐selectivity is catalyst controlled, but oxidant identity, ethylene pressure, and olefin identity influence the ratio of β‐alkenylation to α‐alkenylation. The concentration of HOPiv and naphthalene do not have an effect on the β:α ratio under the reaction conditions tested. Arenes similar to naphthalene (i.e., o‐ xylene and 1,2,3,4‐tetrahydronaphthalene) give quantitative selectivity for alkenylation at the position β to the substituent. Using propylene as the olefin for naphthalene alkenylation, the β:α ratio is 32(7):1. and the anti‐Markovnikov to Markovnikov ratio is 16(2):1.