RESUMO
Reported herein is an unprecedented protocol for C(sp3 )-phosphinylation. With 1â mol % 4CzIPN (1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene) as the catalyst, the visible light induced reaction of redox-active esters of aliphatic carboxylic acids with dimethyl arylphosphonites or diethyl alkylphosphonites at room temperature provides the corresponding decarboxylative phosphinylation products in satisfactory yields. The protocol exhibits broad substrate scope and wide functional-group compatibility, enabling the late-stage modification of complex molecules and rapid synthesis of bioactive phosphinic acids such as glutamine synthetase phosphinothricin and a kynureninase inhibitor. A radical-polar crossover mechanism involving the formation and subsequent oxidation of phosphoranyl radicals followed by nucleophilic demethylation (or deethylation) is proposed.
RESUMO
An efficient phase stabilization method is required in quantum key distribution (QKD) systems for stability in practical applications. The existing active phase compensation method has limitations in multi-node network applications, especially in network-scale applications based on measurement-device-independent QKD systems. In this study, we propose a local active phase compensation scheme that can realize phase compensation independently for each interferometer node. We performed experimental demonstrations in the BB84 phase encoding system based on a Faraday-Michelson interferometer. The average QBER rates of the system under two different forms of the reference light were found to be 1.9% and 1.6%. This scheme can also be applied to other QKD systems and has potential for application in future quantum communication networks.
