Premium
Nickel‐Catalyzed Stereodivergent Synthesis of E ‐ and Z ‐Alkenes by Hydrogenation of Alkynes
Author(s) -
Murugesan Kathiravan,
Bheeter Charles Beromeo,
Linnebank Pim R.,
Spannenberg Anke,
Reek Joost N. H.,
Jagadeesh Rajenahally V.,
Beller Matthias
Publication year - 2019
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.201900784
Subject(s) - alkene , alkyne , catalysis , chemistry , combinatorial chemistry , nickel , selectivity , denticity , homogeneous catalysis , organic chemistry , metal
Abstract A convenient protocol for stereodivergent hydrogenation of alkynes to E ‐ and Z ‐alkenes by using nickel catalysts was developed. Simple Ni(NO 3 ) 2 ⋅6 H 2 O as a catalyst precursor formed active nanoparticles, which were effective for the semihydrogenation of several alkynes with high selectivity for the Z ‐alkene ( Z / E >99:1). Upon addition of specific multidentate ligands (triphos, tetraphos), the resulting molecular catalysts were highly selective for the E ‐alkene products ( E/Z >99:1). Mechanistic studies revealed that the Z ‐alkene‐selective catalyst was heterogeneous whereas the E ‐alkene‐selective catalyst was homogeneous. In the latter case, the alkyne was first hydrogenated to a Z ‐alkene, which was subsequently isomerized to the E ‐alkene. This proposal was supported by density functional theory calculations. This synthetic methodology was shown to be generally applicable in >40 examples and scalable to multigram‐scale experiments.