期刊
ORGANIC PROCESS RESEARCH & DEVELOPMENT
卷 27, 期 4, 页码 775-783出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.oprd.3c00031
关键词
amine-borane; pyridine-boranes; water; green synthesis; solvent selection
In this study, a novel method for the synthesis of amineborane adducts using in situ generated, transient sodium monohydroxyborohydride in ethyl acetate was reported. The synthesis of heteroaromatic pyridine-, 2-picoline-, and 5-ethyl-2-methylpyridine-boranes was successfully demonstrated at 100 mmol scale, as well as pyridineborane at 1.1 mole scale. The substitution of ethyl acetate for tetrahydrofuran as the solvent allows for the activation of sodium borohydride by the aqueous portion of the dual-solvent system, making this green protocol more economically feasible for large-scale production of amine-boranes, as quantitatively demonstrated by the computed green chemistry metrics.
In situ generated, transient sodium monohydroxyborohydride readily reacts with a present amine to form amineborane adducts in ethyl acetate at room temperature. Synthesis of heteroaromatic pyridine-, 2-picoline-, and 5-ethyl-2methylpyridine-boranes, those relevant to large-scale reductive aminations, has been demonstrated at 100 mmol scale, and pyridineborane at 1.1 mole scale. This first report substituting ethyl acetate for tetrahydrofuran, the traditional solvent for amine-borane synthesis, allows for activation of sodium borohydride by the aqueous portion of the heterogeneous dual-solvent system. These factors make this green protocol more economical than those currently available for the large-scale production of amine-boranes as demonstrated, quantitatively, by the computed green chemistry metrics.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据