We report a transition-metal-free and bis(pinacolato)diborane(B_(2)Pin_(2))-promoted transfer hydrogenation of various alkynes to alkanes in high yields with methanol as hydrogen source under mild reaction conditions....We report a transition-metal-free and bis(pinacolato)diborane(B_(2)Pin_(2))-promoted transfer hydrogenation of various alkynes to alkanes in high yields with methanol as hydrogen source under mild reaction conditions.Control experimental results revealed that bis(pinacolato)diborane and methanol played important roles for the transfer hydrogenation of alkynes to alkanes.It is shown that in situ generated borane was the key reductant for the activated alkynes whereas bis(pinacolato)diborane served as strong Lewis acid reagents for diarylacetylenes.More importantly,these transfer hydrogenations could be applied into modifying natural products and a CF_(3)-substituted alkyl group could be easily introduced into complex molecules.The present method highlights mild reaction conditions,broad substrate scope of alkynes,transition-metal free transfer hydrogenation,and gram scalable preparations without column chromatography.展开更多
Whiteflies possess bacterial symbionts Candidatus Portiera aleyrodidium that are housed in specialized cells called bacteriocytes and are faithfully transmitted via the ovary to insect offspring.In one whitefly specie...Whiteflies possess bacterial symbionts Candidatus Portiera aleyrodidium that are housed in specialized cells called bacteriocytes and are faithfully transmitted via the ovary to insect offspring.In one whitefly species studied previously,Bemisia tabaci MEAMI,transmission is mediated by somatic inheritance of bacteriocytes,with a single bacteriocyte transferred to each oocyte and persisting through embryogenesis to the next generation.Here,we investigate the mode of bacteriocyte transmission in two whiefly species,B.tabaci MED,the sister species of MEAM1,and the phylogenetically distant species Trialeurodes vaporariorum.Microsatllite analysis supported by microscopical studies demonstrates that B.tabaci MED bacteriocytes are genetically different from other somatic cells and persist through embryogenesis,as for MEAMI,but T.vaporariorum bacteriocytes are genetically identical to other somatic cells of the insect,likely mediated by the degradation of maternal bacteriocytes in the embryo.These two alternative modes of transmission provide a first demonstration among insect symbioses that the cellular processes underlying vertical transmission of bacterial symbionts can diversify among related host species associated with a single lineage of symbiotic bacteria.展开更多
基金Financial support from the National Natural Science Foundation of China(2257105O)Natural Science Foundation of Guangxi Province(2025GXNSFGA069003,2025GXNSFBA069568,2023GXNSFDA026025)+1 种基金Innovation Project of Guangxi Graduate Education(XYCS2025104)Guangxi Bagui Youth Program is greatly appreciated.
文摘We report a transition-metal-free and bis(pinacolato)diborane(B_(2)Pin_(2))-promoted transfer hydrogenation of various alkynes to alkanes in high yields with methanol as hydrogen source under mild reaction conditions.Control experimental results revealed that bis(pinacolato)diborane and methanol played important roles for the transfer hydrogenation of alkynes to alkanes.It is shown that in situ generated borane was the key reductant for the activated alkynes whereas bis(pinacolato)diborane served as strong Lewis acid reagents for diarylacetylenes.More importantly,these transfer hydrogenations could be applied into modifying natural products and a CF_(3)-substituted alkyl group could be easily introduced into complex molecules.The present method highlights mild reaction conditions,broad substrate scope of alkynes,transition-metal free transfer hydrogenation,and gram scalable preparations without column chromatography.
基金This work was supported by the National Natural Science Foundation of China(Project 31871967)Liaoning and Shenyang High-Level Talent Support Foundation(Project 2018B0078 and RC180025)the Natural Resources Institute,University of Greenwich from a grant provided by the Bill&Melinda Gates foundation(Grant Agreement OPP1058938).
文摘Whiteflies possess bacterial symbionts Candidatus Portiera aleyrodidium that are housed in specialized cells called bacteriocytes and are faithfully transmitted via the ovary to insect offspring.In one whitefly species studied previously,Bemisia tabaci MEAMI,transmission is mediated by somatic inheritance of bacteriocytes,with a single bacteriocyte transferred to each oocyte and persisting through embryogenesis to the next generation.Here,we investigate the mode of bacteriocyte transmission in two whiefly species,B.tabaci MED,the sister species of MEAM1,and the phylogenetically distant species Trialeurodes vaporariorum.Microsatllite analysis supported by microscopical studies demonstrates that B.tabaci MED bacteriocytes are genetically different from other somatic cells and persist through embryogenesis,as for MEAMI,but T.vaporariorum bacteriocytes are genetically identical to other somatic cells of the insect,likely mediated by the degradation of maternal bacteriocytes in the embryo.These two alternative modes of transmission provide a first demonstration among insect symbioses that the cellular processes underlying vertical transmission of bacterial symbionts can diversify among related host species associated with a single lineage of symbiotic bacteria.
