Direct alkylation with skipped enynes or cyclopropropylacetylenes represents an ideal process for the installation of pentadienyl group in terms of atom- and step-economy.The development of catalytic asymmetric versio...Direct alkylation with skipped enynes or cyclopropropylacetylenes represents an ideal process for the installation of pentadienyl group in terms of atom- and step-economy.The development of catalytic asymmetric versions has been frequently pursued and most of the successes have been achieved with enolizable aldehydes.We herein describe a synergistic chiral primary amine/Pd catalysis for asymmetric α-pentadienylation of β-ketocarbonyls and aldehydes with skipped enynes or cyclopropropylacetylenes.The reaction features the construction of acyclic all-carbon quaternary centers with high enantioselectivity,and good functional group tolerance and scalability.展开更多
We report herein the first example of asymmetric hydroazidation of α-substituted vinyl ketones by using chiral primary amines as the catalysts.A simple chiral primary-tertiary diamine catalyst derived from lphenylala...We report herein the first example of asymmetric hydroazidation of α-substituted vinyl ketones by using chiral primary amines as the catalysts.A simple chiral primary-tertiary diamine catalyst derived from lphenylalanine was found to readily promote this aza-Michael addition reaction with enamine protonation as the key stereogenic step,thus enabling the effective synthesis of α-chiral β-azido ketones with good yields and moderate enantioselectivities.展开更多
Herein,we report tunable asymmetric addition and telomerization of butadiene by synergistic chiral primary amine/achiral palladium catalysis.A selection of different achiral phosphine ligand in concert with the chiral...Herein,we report tunable asymmetric addition and telomerization of butadiene by synergistic chiral primary amine/achiral palladium catalysis.A selection of different achiral phosphine ligand in concert with the chiral primary amine-trifluoromethanesulfonic acid(TfOH)conjugates enables both chemo-and enantioselective control of the coupling with butadiene.Bidentate[(oxydi-2,1-phenylene)-bis-(diphenylphosphine)](DPEPhos)ligand led to 1,4-addition adduct whereas monodentate(p-Tol)3P ligand gave the telomerization product.A range ofα-branchedβ-ketoesters and aldehydes could be applied to afford allylation or telomerization products bearing allcarbon quaternary centers at high efficiency and good chemo-,regio-,and stereoselectivities.展开更多
基金the Natural Science Foundation of China(21861132003 and 22031006)Tsinghua University Initiative Scientific Research Program for financial support.
文摘Direct alkylation with skipped enynes or cyclopropropylacetylenes represents an ideal process for the installation of pentadienyl group in terms of atom- and step-economy.The development of catalytic asymmetric versions has been frequently pursued and most of the successes have been achieved with enolizable aldehydes.We herein describe a synergistic chiral primary amine/Pd catalysis for asymmetric α-pentadienylation of β-ketocarbonyls and aldehydes with skipped enynes or cyclopropropylacetylenes.The reaction features the construction of acyclic all-carbon quaternary centers with high enantioselectivity,and good functional group tolerance and scalability.
基金National Natural Science Foundation of China(NSFC Nos.21390400,21521002 and 21502198)the Ministry of Science and Technology,Chinese Academy of Sciences(No.QYZDJSSW-SLH023)for generous financial supportsupported by National Program for Support of Top-notch Young Professionals,CAS Youth Innovation Promotion Association and CAS onehundred talented program(D)
文摘We report herein the first example of asymmetric hydroazidation of α-substituted vinyl ketones by using chiral primary amines as the catalysts.A simple chiral primary-tertiary diamine catalyst derived from lphenylalanine was found to readily promote this aza-Michael addition reaction with enamine protonation as the key stereogenic step,thus enabling the effective synthesis of α-chiral β-azido ketones with good yields and moderate enantioselectivities.
基金the Natural Science Foundation of China(nos.21672217,21861132003,and 22031006)Tsinghua University Initiative Scientific Research Program for financial support.
文摘Herein,we report tunable asymmetric addition and telomerization of butadiene by synergistic chiral primary amine/achiral palladium catalysis.A selection of different achiral phosphine ligand in concert with the chiral primary amine-trifluoromethanesulfonic acid(TfOH)conjugates enables both chemo-and enantioselective control of the coupling with butadiene.Bidentate[(oxydi-2,1-phenylene)-bis-(diphenylphosphine)](DPEPhos)ligand led to 1,4-addition adduct whereas monodentate(p-Tol)3P ligand gave the telomerization product.A range ofα-branchedβ-ketoesters and aldehydes could be applied to afford allylation or telomerization products bearing allcarbon quaternary centers at high efficiency and good chemo-,regio-,and stereoselectivities.
