A highly asymmetric B−H insertion reaction of various diazo compounds with amine‐ and phosphine‐boraneadducts catalyzed by Ru(II)‐Pheox was developed to give chiral organoboranes in high yields (up to 94 %) with high enantioselectivities (up to 98 % ee). It is the first example of a highly enantioselective B−H insertion reaction using a ruthenium catalyst.
Visible light-mediated synthesis of amides from carboxylic acids and amine-boranes
作者:Yu-Qi Miao、Jia-Xin Kang、Yan-Na Ma、Xuenian Chen
DOI:10.1039/d1gc01157j
日期:——
Here, a photocatalytic deoxygenative amidation protocol using readily available amine-boranes and carboxylic acids is described. This approach features mild conditions, moderate-to-good yields, easy scale-up, and up to 62 examples of functionalized amides with diverse substituents. The synthetic robustness of this method was also demonstrated by its application in the late-stage functionalization of
Open-Flask Synthesis of Amine–Boranes via Tandem Amine–Ammonium Salt Equilibration–Metathesis
作者:P. Veeraraghavan Ramachandran、Ameya S. Kulkarni
DOI:10.1021/acs.inorgchem.5b00572
日期:2015.6.15
An amine–ammonium salt equilibration–metathesis sequence provides high-purity amine–boranes in excellent yields from sodium borohydride in refluxing reagent-grade tetrahydrofuran in an open flask.
Nucleophilic displacement of ammonia from ammonia borane for the preparation of alkylamine-, pyridine- and phosphine-boranes
作者:P. Veeraraghavan Ramachandran、Ameya S. Kulkarni
DOI:10.1039/c4ra03397c
日期:——
A near quantitative and safe preparation of a series of aliphatic amine- and phosphine-boranes from ammonia borane (AB) in refluxing THF has been achieved by exploiting the volatility of ammonia. A one-pot preparation of lithium aminoborohydrides from AB has also been described.
Amine-boranes as Dual-Purpose Reagents for Direct Amidation of Carboxylic Acids
作者:P. Veeraraghavan Ramachandran、Henry J. Hamann、Shivani Choudhary
DOI:10.1021/acs.orglett.0c03184
日期:2020.11.6
Amine-boranes serve as dual-purpose reagents for direct amidation, activating aliphatic and aromatic carboxylicacids and, subsequently, delivering amines to provide the corresponding amides in up to 99% yields. Delivery of gaseous or low-boiling amines as their borane complexes provides a major advantage over existing methodologies. Utilizing amine-boranes containing borane incompatible functionalities