Abstract
The field of Ni-catalysed cross-coupling has seen rapid recent growth because of the low cost of Ni, its earth abundance, and its ability to promote unique cross-coupling reactions. Whereas advances in the related field of Pd-catalysed cross-coupling have been driven by ligand design, the development of ligands specifically for Ni has received minimal attention. Here, we disclose a class of phosphines that enable the Ni-catalysed Csp^3 Suzuki coupling of acetals with boronic acids to generate benzylic ethers, a reaction that failed with known ligands for Ni and designer phosphines for Pd. Using parameters to quantify phosphine steric and electronic properties together with regression statistical analysis, we identify a model for ligand success. The study suggests that effective phosphines feature remote steric hindrance, a concept that could guide future ligand design tailored to Ni. Our analysis also reveals that two classic descriptors for ligand steric environment - cone angle and % buried volume - are not equivalent, despite their treatment in the literature.
Original language | English (US) |
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Pages (from-to) | 779-784 |
Number of pages | 6 |
Journal | Nature chemistry |
Volume | 9 |
Issue number | 8 |
DOIs | |
State | Published - Aug 1 2017 |
All Science Journal Classification (ASJC) codes
- General Chemistry
- General Chemical Engineering