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Acene derivatives as a class of polycyclic aromatic hydrocarbons have attracted considerable interest because of their outstanding semiconductor properties. We developed a one-pot synthesis for fully conjugated tetraphene via a sequence of propargyl-allenyl isomerization, phosphine addition, intramolecular Wittig reactions, and Diels–Alder cyclization reactions. The derivative-conjugated aromatic compounds including carbazole or triphenylamine have been constructed via Pd-catalyzed coupling reaction with dibromotetraphene. These compounds show superior photophysical and electrochemical properties, which make them possible candidates for optoelectronic conjugated materials.

A sequence of Rh(III)-catalyzed C—H activation, 1,5-H shift, intramolecular allene insertion and protonolysis provides a facile synthesis of thiepine sulfones.

Polycyclic skeletons are present in numerous important compounds, such as synthetic intermediates and target molecules of biological interest. In this paper, a Selectfluor-promoted construction of polycyclic skeletons with high synthetic efficiency was developed.

An efficient metal-free procedure for the synthesis of 4-diphenylphosphoryl)methyl-2,3-dihydro-1H-pyrroles and furans was developed via a sequence of propargyl–allenyl isomerization and Alder ene reaction. The Wittig-type olefination transformation of the phosphine oxide moiety to the vinyl group with high stereoselectivity was further investigated.

Allenylphosphonium species, reactive Michael acceptors, could be generated from simple, readily available propargylphosphonium salts through propargyl–allenyl isomerization. We developed an efficient synthesis for cyclopentenes, pyrroles, and thiophenes via a sequence of propargyl–allenyl isomerizations, Michael additions, and intramolecular Wittig reactions.

The synthesis of polysubstituted oxazolines is of great interest due to the synthetic and pharmaceutical importance. We developed a sequence of Pummerer/Michael reactions for the stereoselective synthesis of 5-(1-(arylthio)vinyl)-oxazolines.

The title method is advantageous with regards to simple operation and ready availability of starting materials.

The derivative (VI) can smoothly be converted into the biologically important fused compound (VII).

A facile and efficient synthesis of medium rings via a bicyclic sulfonium ion was developed. Spectroscopic evidence for the formation of an intermediate sulfonium moiety is provided. The sulfur atom served as a “bridge” to access the medium ring system and could be removed after use via a Ramberg–Backlund process. As a result of the readily available starting materials, simple operation, and mild conditions, these reactions should be an appealing strategy in organic synthesis.

Coupling of bromides (I) and (IV) with alkynes is followed by cyclization of the non-isolable intermediate to give the desired substituted pyrrole structures.

A sulfur-assisted and 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU)-catalyzed cyclization of 2-alkynylanilines for the metal-free synthesis of indole derivatives is reported. As a result of the metal-free process, the ready availability of the starting materials and the simple and convenient operation, the type of reaction presented here has potential utility in organic synthesis. A 10-gram scale preparation may demonstrate the possibility of its application in the environmentally friendly synthesis of indole derivatives.

Treatment of enediynes like (I), (III), and (V) with NEt3 and Ga(OTf)3 is found to allow simple and efficient access to dihydrobenzo[c]thiophene derivatives.

A sulfur-assisted five-cascade sequential reaction, wherein the in situ-generated allenyl allyl sulfides undergo thio-Claisen rearrangement, intramolecular Michael addition, and 1, 5-proton migration/aromatization to obtain allyl thiophen-2-yl acetates, propionates, and ketones as the final products, was reported. As a result of the ready availability of starting materials and the extremely simple and convenient operation, this type of reaction presented here has potential utility in organic synthesis. Application of this efficient method for the synthesis of potentially pharmaceutical compounds also might be useful for the pharmacists.

A simple and facile Pummerer cyclization for the synthe- sis of substituted 5-(2-(phenylthio)vinyl)-1,3-oxazoles, which are common substructures in numerous biologically active compounds, synthetic intermediates, and pharmaceuticals, has been developed.

An intramoluclar addition of sulfur-participated Nazarov-type cyclization affording 3-thio-1H-indenes was reported. As a result of the ready availability of the starting materials and the simple and convenient operation, the type of reaction presented here has potential utility in organic synthesis.

A facile and efficient method for the synthesis of 2,4-dihalo-3-thio-furans via the electrophilic cyclization and 1,2-migration of the thio group of 4-thio-but-2-yn-1-ols was developed. As a result of the ready availability of starting materials and the simple and convenient operation, this synthetic route would have potential utility in organic synthesis.

Alkylidenecyclopropanes undergo CAN-mediated addition reactions with 1,3-dicarbonyl compounds or ring rearrangement reactions leading to dihydrofuran and cyclobutanone derivatives, respectively, in moderate yields.

Alkylidenecyclopropanes undergo Mn(OAc)3-mediated addition with malonate, leading to dihydronaphthalene derivatives in moderate yields.

N-[(E)-Homocinnamyl] amides were stereoselectively synthesized by the reaction of the methylenecyclopropanes (MCPs) with nitriles under acidic conditions in moderate yields in a one-pot manner.

A convenient and efficient method for the synthesis of (Z)-2,4-dihalobutenes, a useful building block in organic synthesis, was reported in good yield by the reaction of alkylidenecyclopropanes and CuX 2 (or CuI/I 2 ).

[reaction: see text] A mixture of cyclopropylideneacetic acids (or esters) and CuBr(2) (or CuI/I(2)) in aqueous acetonitrile afforded 4-substituted 2(5H)-furanones or 3,4-substituted 5,6-dihydro-2H-pyran-2-ones in moderate to good yields. The selectivity of the reaction greatly depended on the reaction temperature.