title: Nickel-Catalyzed Allylic Alkylation with Diarylmethane Pronucleophiles: Reaction Development and Mechanistic Insights.
abstract: Palladium-catalyzed allylic substitution reactions are among the most efficient methods to construct C-C bonds between sp(3)-hybridized carbon atoms. In contrast, much less work has been done with nickel catalysts, perhaps because of the different mechanisms of the allylic substitution reactions. Palladium catalysts generally undergo substitution by a "soft"-nucleophile pathway, wherein the nucleophile attacks the allyl group externally. Nickel catalysts are usually paired with "hard" nucleophiles, which attack the metal before C-C bond formation. Introduced herein is a rare nickel-based catalyst which promotes substitution with diarylmethane pronucleophiles by the soft-nucleophile pathway. Preliminary studies on the asymmetric allylic alkylation are promising.
authors.affiliation: Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, 19104-6323, USA.
authors.forename: Sheng-Chun
authors.initials: SC
authors.lastname: Sha
authors.affiliation: Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, 19104-6323, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, 19104-6323, USA.
authors.forename: Jianyou
authors.initials: J
authors.lastname: Mao
authors.affiliation: Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, 19104-6323, USA.
authors.forename: Ana
authors.initials: A
authors.lastname: Bellomo
authors.affiliation: Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, 19104-6323, USA.
authors.forename: Soo A
authors.initials: SA
authors.lastname: Jeong
authors.affiliation: Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, 19104-6323, USA. pwalsh@sas.upenn.edu.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Walsh
mesh_terms: D000478:Alkylation; D002384:Catalysis; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D009532:Nickel / Q000737:chemistry*
chemical_list: D009532:Nickel; D008697:Methane
keywords: allylic compounds; asymmetric catalysis; cross-coupling; nickel; synthetic methods