B-Alkyl Suzuki−Miyaura Cross-Coupling Reactions with Air-Stable Potassium Alkyltrifluoroborates

Abstract

The palladium-catalyzed cross-coupling reaction of substituted potassium alkyltrifluoroborates with aryl halides and aryl triflates proceeds readily with moderate to good yields. The potassium alkyltrifluoroborates 1, 2, and 3a-e were easily synthesized and obtained as air-stable crystalline solids that can be stored for long periods of time. All of the cross-couplings proceed under the same reaction conditions using PdCl(2)(dppf).CH(2)Cl(2) as catalyst in THF-H(2)O in the presence of 3 equiv of Cs(2)CO(3) as base.

Suzuki–Miyaura Cross‐Coupling Reactions of Alkylboronic Acid Derivatives or Alkyltrifluoroborates with Aryl, Alkenyl or Alkyl Halides and Triflates

“…Finally, couplings of aryl or alkenyl triflates with primary alkyl trifluoroborates have been reported by Molander and co-workers (Scheme 72 and Scheme 73). [91,100,101] Yields very similar to those obtained with aryl bromides were observed. Several functionalities on the alkyl trifluoroborates and/or the aryl or alkenyl triflates are tolerated.…”

“…[89] For example, they have reported cross-couplings of methyl trifluoroborate, trimethylsilyl trifluoroborate or 2-phenylethyl trifluoroborate with a wide variety of aryl bromides (Scheme 65). [91] Good yields were in most cases obtained in the presence of electron-deficient aryl bromides. With electron-rich aryl bromides, on the other hand, the reactions generally led to lower yields.…”

Organotrifluoroborates and Monocoordinated Palladium Complexes as Catalysts—A Perfect Combination for Suzuki–Miyaura Coupling

“…When the [PdCl 2 -(dppf)]·CH 2 Cl 2 system is used, 9 mol% of the catalyst system is required to react with more reactive, electron-poor aryl bromides. [73]…”

Ferrocenylmethylphosphines ligands in the palladium-catalysed synthesis of methyl propionate

“…

The synthesis of a range of novel ferrocenylmethylphosphanes ligands is described which have direct application in the palladium catalysed reaction of carbon monoxide, methanol and ethene to obtain methyl propionate, a key intermediate in the preparation of methylmethacrylate.Ferrocenylphosphanes continue to be of considerable interest as ligands in a range of transition-metal catalysed processes and have made inroads into industrial applications [1] in additon to their well documented use in academic research protocols [2]. The pre-eminent ligand classes of ferrocenyl phosphanes are the 1,1 0 -disubstituted and 1,2-disubstituted ferrocenes such as dppf, ppfa, and josiphos, respectively [3].

…”

“…Ferrocenylphosphanes continue to be of considerable interest as ligands in a range of transition-metal catalysed processes and have made inroads into industrial applications [1] in additon to their well documented use in academic research protocols [2]. The pre-eminent ligand classes of ferrocenyl phosphanes are the 1,1 0 -disubstituted and 1,2-disubstituted ferrocenes such as dppf, ppfa, and josiphos, respectively [3].…”