Asymmetric ring-expansion reactions of silacyclobutanes(SCBs)with alkynes have evolved as one of the powerful protocols for the construction of silicon-stereogenic compounds.However,the achievement of highly enantiose...Asymmetric ring-expansion reactions of silacyclobutanes(SCBs)with alkynes have evolved as one of the powerful protocols for the construction of silicon-stereogenic compounds.However,the achievement of highly enantioselective annulation of SCBs with terminal alkynes remains a challenge.Herein,we report a rhodium-catalyzed asymmetric annulation reaction of SCBs with terminal alkynes,which relies on the newly identified chiral sulfinamide phosphine ligand Ming-Phos.This catalytic system exhibits unique effects under mild conditions,leading to the direct synthesis of structurally diverse chiral silacycles in moderate to good yields with high enantioselectivities(up to 95%ee).展开更多
Iodine extravasation is commonly seen in stroke patients after successful mechanical thrombectomy.Iodine extravasation may be associated with patient prognosis,and more iodine extravasation is highly associated with t...Iodine extravasation is commonly seen in stroke patients after successful mechanical thrombectomy.Iodine extravasation may be associated with patient prognosis,and more iodine extravasation is highly associated with the development of severe hemorrhagic transformation(HT).Hence,it is essential to identify early hemorrhage after intra-artery therapy and the imaging indicators that can predict late hemorrhage transformation.展开更多
基金the funding support of the National Key R&D Program of China(No.2021YFF0701601)NSFC(Nos.22031004 and 21921003)+1 种基金Shanghai Municipal Education Commission(No.20212308)Science and Technology Commission of Shanghai Municipality(No.23ZR1404800).
文摘Asymmetric ring-expansion reactions of silacyclobutanes(SCBs)with alkynes have evolved as one of the powerful protocols for the construction of silicon-stereogenic compounds.However,the achievement of highly enantioselective annulation of SCBs with terminal alkynes remains a challenge.Herein,we report a rhodium-catalyzed asymmetric annulation reaction of SCBs with terminal alkynes,which relies on the newly identified chiral sulfinamide phosphine ligand Ming-Phos.This catalytic system exhibits unique effects under mild conditions,leading to the direct synthesis of structurally diverse chiral silacycles in moderate to good yields with high enantioselectivities(up to 95%ee).
基金This study was supported by a grant from the Deyang City Science and Technology Research Foundation(No.2018SZS059)。
文摘Iodine extravasation is commonly seen in stroke patients after successful mechanical thrombectomy.Iodine extravasation may be associated with patient prognosis,and more iodine extravasation is highly associated with the development of severe hemorrhagic transformation(HT).Hence,it is essential to identify early hemorrhage after intra-artery therapy and the imaging indicators that can predict late hemorrhage transformation.
