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An efficient and metal-free strategy for the synthesis of spiro-fused indanolactones/lactams has been developed for the reaction of arynes with α-chloroacetyl lactones/lactams. This strategy provides access to spiroindanone derivatives via aryne insertion/spirocyclization.

We report the efficient synthesis of cycloalkyl-fused naphthalenes through the [4 + 2]-cycloaddtion/decarboxylative aromatization of alkyne-tethered aryne insertion adducts. These scaffolds were difficult to synthesize using conventional reactions. The reaction proceeds via the formation of a benzopyrylium intermediate followed by intramolecular [4 + 2] cycloaddition and a subsequent decarboxylation pathway. This method is also compatible with allene-tethered substrates to afford similar products. In addition, the one-pot synthesis of polysubstituted naphthalenes via aryne insertion/benzannulation has also been developed in good yield.

A domino approach to bridged cycloocta[b]indolone through a cascade of aza-Piancatelli rearrangement/Friedel-Crafts alkylation is developed. This transformation has been realized by reaction of an indole-tethered 2-furylcarbinol and substituted aniline in the presence of a Lewis acid to initiate aza-Piancatelli rearrangement followed by an in situ intramolecular Friedel-Crafts alkylation to access bridged tetracyclic frameworks in one pot.

A serendipitous synthesis of N-substituted 2-amino-2'-hydroxy-1,1'-biaryls through an aryne annulation with indolyl β-ketonitrile/ester in a cascade manner is demonstrated. The reaction sequence involves benzyne-mediated [2 + 2] Stoltz-type cycloaddition-cleavage and intramolecular Michael addition followed by C-N bond cleavage under transition-metal-free reaction conditions. Interestingly, while [4 + 2] Diels-Alder reaction is a possible pathway, no traces of the regioisomer was isolated.

A domino approach to bridged cycloocta[

A chiral-template-driven intramolecular Diels-Alder reaction has been used to build the tricyclic core of kalihinols, a group of antimalarial marine natural products. The key starting materials are commercially available nerol and sulcatone.

Benzyne insertion to build the privileged scaffold of a [6.8.6]-tricyclic framework on polycyclic and sp3-rich natural products has been developed. The formation of the [6.8.6]-tricyclic ring system is solvent dependent.

Short and scalable synthesis of the complex pentacyclic indolosesquiterpene natural product mycoleptodiscin A has been achieved from commercially available diterpenoid (+)-sclareolide in 19% overall yield. This approach allows one to prepare various analogues of mycoleptodiscin using McMurry cyclization as a key reaction with just three chromatographic purifications.

The first stereocontrolled and enantiospecific formal synthesis of antiplatelet drug beraprost has been achieved from readily available 1-tetralone.

The divergent and enantioselective total synthesis of the powerful antifungal marine natural product bengazole A has been achieved.

A combination of "chiron" and "asymmetric" approaches is utilized to construct the southern (C 9-C 25) region of marine natural product spirastrellolide B. The key functionalities are derived from d-glucose and Sharpless asymmetric epoxidation and dihydroxylation.

An enantioselective synthesis of natural anticancer macrolide pladienolide B is described. The synthetic highlights include Sharpless asymmetric epoxidation, ring closing metathesis (RCM), Ireland–Claisen rearrangement, Shi epoxidation, and Pd-catalyzed Stille coupling as key steps. The synthetic route also allowed the synthesis of the truncated analogues (41a–d) of pladienolide B.

International audience; The redox isomerization processes and tandem isomerization-aldolization reactions, mediated by nickel catalysts, offer new versatile entries to acylsilanes. For the second reaction, high diastereoselectivities, up to 98:2, have been obtained with bulky substituents on silicon.

[reaction: see text] PEG has been used as a solvent medium for regioselective Heck reactions with easy recyclability of solvent and Pd catalyst for the first time.

An efficient new entry toward the construction of 3-substituted 1,2,3,4-tetrahydroisoquinolines from N,N-dibenzyl-α-aminols is reported via intramolecular Friedel−Crafts cyclization of in situ generated tosylate intermediate.