Catalytic Enantioselective Intermolecular Hydroacylation: Rhodium-Catalyzed Combination of β-S-Aldehydes and 1,3-Disubstituted Allenes
摘要:
A rhodium(I) catalyst incorporating the Me-DuPhos ligand promotes enantioselective intermolecular hydroacylation between P-S-aldehydes and 1,3-disubstituted allenes. The nonconjugated enone products are obtained in good yields and with high enantioselectivities.
A transition-metal-free three-component process that combines aldehydes, 3-(tributylstannyl)propargyl acetates formed in situ from readily available propargyl acetates, and trialkylboranes provides access to a range of 1,2,4-trisubstituted homopropargylic alcohols. The addition of diisopropylamine plays a crucial role in the selective formation of homopropargylic alcohols. Importantly, this methodology
Highly Regioselective Palladium-Catalyzed Thiocarbonylation of Allenes with Thiols and Carbon Monoxide
作者:Wen-Jing Xiao、Giuseppe Vasapollo、Howard Alper
DOI:10.1021/jo972121w
日期:1998.4.1
CHCl(3)-PPh(3), Pd(PPh(3))(4), and Pd(OAc)(2)-dppp are also effective for this reaction. The thiocarbonylation reaction is believed to proceed via an allylpalladium intermediate. The reaction exhibits high regioselectivity, in which the thiophenyl group adds to the less substituteddouble bond of allenes to give beta,gamma-unsaturated thioesters.
Reactions of 3-alkyl- and 3,3-dialkyl-1-bromoallenes with organocuprates: Effects of the nature of the cuprate reagent on the regio- and stereoselectivity
作者:Anna Maria Caporusso、Carmela Polizzi、Luciano Lardicci
DOI:10.1016/s0040-4039(00)96867-9
日期:1987.1
Organocuprates induce 1,3- and direct substitution in 3-alkyl- and 3,3-dialkyl-1-bromo-1,2-dienes leading respectively to either terminal acetylenes or allenic hydrocarbons. The nature of the cuprate exerts a prominent role in determining both the regio- and the stereochemistry of these reactions.
Gold(I)-Catalyzed Stereoconvergent, Intermolecular Enantioselective Hydroamination of Allenes
作者:Kristina L. Butler、Michele Tragni、Ross A. Widenhoefer
DOI:10.1002/anie.201201584
日期:2012.5.21
Gold and silver: A 1:2 mixture of [(S)‐1}(AuCl)2] and AgBF4 catalyzes the enantioselectivehydroamination of chiral, racemic 1,3‐disubstituted allenes with N‐unsubstituted carbamates to form N‐allylic carbamates in good yield, with high regio‐ and diastereoselectivity, and up to 92 % ee (see scheme, Cbz=benzyloxycarbonyl).
Rh(I)-Catalyzed Insertion of Allenes into C–C Bonds of Benzocyclobutenols
作者:Chunliang Zhao、Li-Chuan Liu、Jing Wang、Chenran Jiang、Qing-Wei Zhang、Wei He
DOI:10.1021/acs.orglett.5b03518
日期:2016.1.15
Herein we report a Rh(I)-catalyzed two carbon insertion into C–C bonds of benzocyclobutenols by employing symmetrical and unsymmetrical allenes. This reaction provides rapid access to alkylidene tetralins bearing two adjacent stereogenic centers in good yields and diasteroselectivities.