Jiang-Lin Hu

Bio: Jiang-Lin Hu is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Cycloaddition & Cyclobutanes. The author has an hindex of 4, co-authored 7 publications receiving 266 citations.

Asymmetric Annulation of Donor–Acceptor Cyclopropanes with Dienes

Abstract: An efficient [4 + 3] cycloaddition reaction of D–A cyclopropanes with dienes has been successfully developed. The reaction proceeds well with various dienolsilyl ethers in the presence of Lewis acid, delivering a variety of cycloheptenes and [n,5,0]carbobicycles with excellent stereoselectivity. The asymmetric version of this reaction is also realized using a newly designed chiral Cy-TOX ligand, providing a new approach to access optically active cycloheptenes and [n,5,0]carbobicycles. Mechanisic study reveals that the reaction involves a stepwise pathway, which undergoes an unusual ring opening of five-membered [3 + 2] intermediate and sequential intramolecular cyclization to afford the thermodynamically stable [4 + 3] annulation product.

Enantioselective Construction of Cyclobutanes: A New and Concise Approach to the Total Synthesis of (+)-Piperarborenine B

Abstract: A highly diastereoselective and enantioselective Cu(II)/SaBOX-catalyzed [2 + 2] cycloaddition of methylidenemalonate and multisubstituted alkenes was developed to furnish optically active cyclobutanes in high yields with >99/1 dr and up to >99% ee. By application of the newly developed method, the total synthesis of (+)-piperarborenine B was completed in eight steps from methylidenemalonate and olefin in 17% overall yield with >99/1 dr and 99% ee.

Copper Catalyzed Asymmetric [4 + 2] Annulations of D-A Cyclobutanes with Aldehydes

Abstract: Copper catalyzed enantioselective [4 + 2] annulations of D-A cyclobutanes and aldehydes have been developed. In the presence of a side arm modified chiral bisoxazoline (SaBOX) ligand, the [4 + 2] annulations proceeded smoothly with a broad substrate scope. 22 examples was studied, leading to the corresponding products with various functional groups in 41-99% yields with >99/1 dr and 90-96% ee. The resulting product with two ester groups was mono-reduced, giving the corresponding product in excellent diastereoselectivity without loss of the enantiopurity.

Asymmetric Annulation of Donor—Acceptor Cyclopropanes with Dienes.

Abstract: Donor-acceptor substituted cyclopropanes are efficiently transformed with dienolsilyl ethers in the presence of a newly designed chiral bisoxazoline ligand.

Bidentate Directing Groups: An Efficient Tool in C-H Bond Functionalization Chemistry for the Expedient Construction of C-C Bonds.

Abstract: During the past decades, synthetic organic chemistry discovered that directing group assisted C–H activation is a key tool for the expedient and siteselective construction of C–C bonds. Among the v...

Construction of Nine-Membered Heterocycles through Palladium-Catalyzed Formal [5+4] Cycloaddition

Abstract: The first catalytic formal [5+4] cycloaddition to prepare nine-membered heterocycles is presented. Under palladium catalysis, the reaction of N-tosyl azadienes and substituted vinylethylene carbonates (VECs) proceeds smoothly to produce benzofuran-fused heterocycles in uniformly high efficiency. Highly diastereoselective functionalization of the nine-membered heterocycles through peripheral attack is also demonstrated.

Catalytic Enantioselective Ring-Opening Reactions of Cyclopropanes.

Abstract: This review describes the development of enantioselective methods for the ring opening of cyclopropanes. Both approaches based on the reaction of nonchiral cyclopropanes and (dynamic) kinetic resolutions and asymmetric transformations of chiral substrates are presented. The review is organized according to substrate classes, starting by the more mature field of donor-acceptor cyclopropanes. Emerging methods for enantioselective ring opening of acceptor- or donor-only cyclopropanes are then presented. The last part of the review describes the ring opening of more reactive three-membered rings substituted with unsaturations with a particular focus on vinylcyclopropanes, alkylidenecyclopropanes, and vinylidenecyclopropanes. In the last two decades, the field has grown from a proof of concept stage to a broad range of methods for accessing enantioenriched building blocks, and further extensive developments can be expected in the future.

Stereoselective 1,6-Conjugate Addition/Annulation of para-Quinone Methides with Vinyl Epoxides/Cyclopropanes

Abstract: Here, we present an unprecedented formal [3 + 2] cycloaddition of para-quinone methides with vinyl epoxides/cyclopropanes to deliver a wide range of spiro[4.5]decanes in high efficiency and stereoselectivity. The commercial availability of the catalysts and reagents, together with the convenient procedure, makes it an attractive method in asymmetric synthesis.

Catalytic Asymmetric (4+3) Cyclizations of In Situ Generated ortho-Quinone Methides with 2-Indolylmethanols.

Abstract: The first catalytic asymmetric (4+3) cyclization of in situ generated ortho-quinone methides with 2-indolylmethanols has been established, which constructed seven-membered heterocycles in high yields (up to 95 %) and excellent enantioselectivity (up to 98 %). This approach not only represents the first catalytic asymmetric (4+3) cyclization of o-hydroxybenzyl alcohols, but also enabled an unprecedented catalytic asymmetric (4+3) cyclization of 2-indolylmethanols. In addition, a scarcely reported catalytic asymmetric (4+3) cyclization of para-quinone methide derivatives was accomplished.