An efficient synthesis of functionalized 1,3-dienes via one-pot reactions between dialkyl acetylenedicarboxylates, 1,3-dicarbonyl compounds and secondary amines in water as the solvent is described. The mild reaction ...An efficient synthesis of functionalized 1,3-dienes via one-pot reactions between dialkyl acetylenedicarboxylates, 1,3-dicarbonyl compounds and secondary amines in water as the solvent is described. The mild reaction condition high yields and the new products are advantages of our method.展开更多
We report a palladium-catalyzed formal intermolecular [4＋2] cycloaddition of benzoic and acrylic acids with 1,3-dienes including the stock chemicals 1,3-butadiene and isoprene leading to synthetically useful 3,4-dihy...We report a palladium-catalyzed formal intermolecular [4＋2] cycloaddition of benzoic and acrylic acids with 1,3-dienes including the stock chemicals 1,3-butadiene and isoprene leading to synthetically useful 3,4-dihydroisocoumarins and 5,6-dihydrocoumalins. Stepwise C-H bond cleavage and annulation are likely involved in the reaction pathway. The synthetic potential of the methodology was demonstrated by two short derivatizations and total synthesis of natural product Clausamine B.展开更多
A new palladium-catalyzed selective aminomethylation of conjugated 1,3-dienes with aminais via double C-N bond activation is described. This simple method provides an effective and rapid approach for the synthesis of ...A new palladium-catalyzed selective aminomethylation of conjugated 1,3-dienes with aminais via double C-N bond activation is described. This simple method provides an effective and rapid approach for the synthesis of linear a,13-unsaturated allylic amines with perfect regioselectivity. Mechanistic studies disclosed that one palladium catalyst cleaved two distinct C-N bond to furnish a cascade double C-N bond activation, in which an allylic 1,3-diamine and allylic 1,2-diamine were initially formed as key intermediates through the palladium-catalyzed C-N bond activation of aminal and the α,β-unsaturated allylic amine was subsequently produced via palladium-catalyzed C-N bond activation of the allylic diamines.展开更多
Phenylseleno- and p-tolylsulfonyl substituted 1,3-dienes were conveniently prepared with high stereoselectivity by the elimination reaction of phenylseleno- and p-tolylsulfonyl substituted allyl alcohols in the presen...Phenylseleno- and p-tolylsulfonyl substituted 1,3-dienes were conveniently prepared with high stereoselectivity by the elimination reaction of phenylseleno- and p-tolylsulfonyl substituted allyl alcohols in the presence of BF3·Et2O in acetic anhydride. The products were characterized by 1H NMR, MS, IR and elemental analysis. The single crystal structure of 2a was determined by X-ray diffraction analysis.展开更多
（E）-α-Stannylvinyl phenyl（or p-tolyl）sulfones underwent an iododestannylation reaction to afford （E）-α-iodovinyl phenyl（or p-tolyl）sulfones 1, which reacted with （E）-alkenylzirconium（IV） complexes 2 prod...（E）-α-Stannylvinyl phenyl（or p-tolyl）sulfones underwent an iododestannylation reaction to afford （E）-α-iodovinyl phenyl（or p-tolyl）sulfones 1, which reacted with （E）-alkenylzirconium（IV） complexes 2 produced in situ by hydrozirconation of terminal alkynes in the presence of a Pd（PPh3）4 catalyst to afford stereoselectively （1Z,3E）-2- phenyl（or p-tolyl）sulfonyl-substituted 1,3-dienes 3 in good yields.展开更多
A convenient and practical route to functionalized conjugated 1,3-enynes and 1,3-dienes is described. 1,4-Bis（heteroaryl）- 1,3-diene and 1-heteroarylbut- 1-en-3-yne derivatives were prepared from 1,4-dichloro-2-buty...A convenient and practical route to functionalized conjugated 1,3-enynes and 1,3-dienes is described. 1,4-Bis（heteroaryl）- 1,3-diene and 1-heteroarylbut- 1-en-3-yne derivatives were prepared from 1,4-dichloro-2-butyne and corresponding N-heteroarenes such as imidazole, pyrrole, pyrazole and indole derivatives in the presence of bases in good to high yields.展开更多
Because of the widespread applications of optically active alkyl fluorides in medicinal and agro chem-icals,enantioselective and even stereodivergent construction of alkyl fluorides remains highly desirable but underd...Because of the widespread applications of optically active alkyl fluorides in medicinal and agro chem-icals,enantioselective and even stereodivergent construction of alkyl fluorides remains highly desirable but underdeveloped.Transition-metal-catalyzed asymmetric hydrofluoroalkylation of readily available di-enes represents a novel route to achieve this goal,yet receives scarce study.Here we report an intrigu-ing palladium-catalyzed enantioselective hydromonofluoroalkylation reaction of conjugated dienes.Both monosubstituted and internal dienes proceed well with the transformation and furnish alkyl fluorides in generally>80%yield and>90%ee.A stereodivergent hydromonofluoroalkylation protocol via Pd/Cu co-catalysis is also established for the access to all four stereoisomers of corresponding moieties bear-ing a fully-substituted F-stereogenic center and vicinal tertiary carbon center.In addition,asymmetric migratory hydromonofluoroalkylation of skipped dienes is developed to realize the direct allylic C-H flu-oroalkylation.A compound library of enantioenriched cyclic fluorides is thus built to highlight the trans-formation potential of present methodology.展开更多
基金国家重点研发项目(2022YFA1503200,2021YFC2101901)国家自然科学基金(22122103,21971108,21971111,22271144)+1 种基金中央高校基本科研业务费(020514380304,020514380252 and 020514380272)江苏省研究生科研与实践创新计划项目(KYCX22_0100).
基金supported by the National Natural Science Foundation of China(21732006,51821006,21927814)the CAS Collaborative Innovation Program of Hefei Science Center(2021HSC-CIP004)the University Synergy Innovation Program of Anhui Province(GXXT-2021-023)。
文摘An efficient synthesis of functionalized 1,3-dienes via one-pot reactions between dialkyl acetylenedicarboxylates, 1,3-dicarbonyl compounds and secondary amines in water as the solvent is described. The mild reaction condition high yields and the new products are advantages of our method.
基金We are grateful to the National Natural Science Foundation of China （Nos. 21772218, 21421091, XDB20000000）, the ＂Thousand Plan＂ Youth program, State Key Laboratory of Organome-tallic Chemistry, Shanghai Institute of Organic Chemistry and the Chinese Academy of Sciences.
文摘We report a palladium-catalyzed formal intermolecular [4＋2] cycloaddition of benzoic and acrylic acids with 1,3-dienes including the stock chemicals 1,3-butadiene and isoprene leading to synthetically useful 3,4-dihydroisocoumarins and 5,6-dihydrocoumalins. Stepwise C-H bond cleavage and annulation are likely involved in the reaction pathway. The synthetic potential of the methodology was demonstrated by two short derivatizations and total synthesis of natural product Clausamine B.
基金This research was supported by the National Natural Science Foundation of China （Nos. 21672199 and 21790333） and CAS Interdisciplinary Innovation Team.
文摘A new palladium-catalyzed selective aminomethylation of conjugated 1,3-dienes with aminais via double C-N bond activation is described. This simple method provides an effective and rapid approach for the synthesis of linear a,13-unsaturated allylic amines with perfect regioselectivity. Mechanistic studies disclosed that one palladium catalyst cleaved two distinct C-N bond to furnish a cascade double C-N bond activation, in which an allylic 1,3-diamine and allylic 1,2-diamine were initially formed as key intermediates through the palladium-catalyzed C-N bond activation of aminal and the α,β-unsaturated allylic amine was subsequently produced via palladium-catalyzed C-N bond activation of the allylic diamines.
基金Project supported by the National Natural Science Foundation of China (No. 20272050).
文摘Phenylseleno- and p-tolylsulfonyl substituted 1,3-dienes were conveniently prepared with high stereoselectivity by the elimination reaction of phenylseleno- and p-tolylsulfonyl substituted allyl alcohols in the presence of BF3·Et2O in acetic anhydride. The products were characterized by 1H NMR, MS, IR and elemental analysis. The single crystal structure of 2a was determined by X-ray diffraction analysis.
基金Project supported by the National Natural Science Foundation of China （No. 20462002） and the Natural Science Foundation of Jiangxi Province in China （No. 0420015）.
文摘（E）-α-Stannylvinyl phenyl（or p-tolyl）sulfones underwent an iododestannylation reaction to afford （E）-α-iodovinyl phenyl（or p-tolyl）sulfones 1, which reacted with （E）-alkenylzirconium（IV） complexes 2 produced in situ by hydrozirconation of terminal alkynes in the presence of a Pd（PPh3）4 catalyst to afford stereoselectively （1Z,3E）-2- phenyl（or p-tolyl）sulfonyl-substituted 1,3-dienes 3 in good yields.
基金Project supported by the National Natural Science Foundation ofChina （No. 20572096） and Zhejiang Provincial Natural Science Foundation （No. R405066）.
文摘A convenient and practical route to functionalized conjugated 1,3-enynes and 1,3-dienes is described. 1,4-Bis（heteroaryl）- 1,3-diene and 1-heteroarylbut- 1-en-3-yne derivatives were prepared from 1,4-dichloro-2-butyne and corresponding N-heteroarenes such as imidazole, pyrrole, pyrazole and indole derivatives in the presence of bases in good to high yields.
基金the National Natural Science Foundation of China(NSFC,No.22071262)Science and Technology Commission of Shanghai Municipality(No.22ZR1475200)+1 种基金Shanghai Rising-Star program(No.20QA1411300)CAS Key Laboratory of Synthetic Chemistry of Natural Substances,and Shanghai Institute of Organic Chemistry for financial support.
文摘Because of the widespread applications of optically active alkyl fluorides in medicinal and agro chem-icals,enantioselective and even stereodivergent construction of alkyl fluorides remains highly desirable but underdeveloped.Transition-metal-catalyzed asymmetric hydrofluoroalkylation of readily available di-enes represents a novel route to achieve this goal,yet receives scarce study.Here we report an intrigu-ing palladium-catalyzed enantioselective hydromonofluoroalkylation reaction of conjugated dienes.Both monosubstituted and internal dienes proceed well with the transformation and furnish alkyl fluorides in generally>80%yield and>90%ee.A stereodivergent hydromonofluoroalkylation protocol via Pd/Cu co-catalysis is also established for the access to all four stereoisomers of corresponding moieties bear-ing a fully-substituted F-stereogenic center and vicinal tertiary carbon center.In addition,asymmetric migratory hydromonofluoroalkylation of skipped dienes is developed to realize the direct allylic C-H flu-oroalkylation.A compound library of enantioenriched cyclic fluorides is thus built to highlight the trans-formation potential of present methodology.
