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The synthesis of mono-, di-, and trifluoromethyl aryl ethers by fluorodecarboxylation of the corresponding carboxylic acids is reported. AgF2 induces decarboxylation of aryloxydifluoroacetic acids, and AgF, either generated in situ or added separately, serves as a source of fluorine to generate the fluorodecarboxylation products. The addition of 2,6-difluoropyridine increased the reactivity of AgF2 , thereby increasing the range of functional groups and electronic properties of the aryl groups that are tolerated. The reaction conditions used for the formation of trifluoromethyl aryl ethers also served to form difluoromethyl and monofluoromethyl aryl ethers.

Two new compounds, 11,11′-dimer of scopoletin ( 1 ) and 11- O - β -glucopyranosylhamaudol ( 2 ), together with seven known compounds were isolated and identified from the whole grass of Cicuta virosa . The chemical structures of the isolated compounds were elucidated using different spectroscopic methods. In addition, the chemical constituents were evaluated for multidrug resistance reversing activity towards doxorubicin-resistant K562/A02 cells. Compounds 1 , 8 , and 9 were endowed with remarkable MDR reversing effects.

Silacyclobutane was discovered to be an efficient C−H bond silylation reagent. Under the catalysis of RhI/TMS-segphos, silacyclobutane undergoes sequential C−Si/C−H bond activations, affording a series of π-conjugated siloles in high yields and regioselectivities. The catalytic cycle was proposed to involve a rarely documented endocyclic β-hydride elimination of five-membered metallacycles, which after reductive elimination gave rise to a Si−RhI species that is capable of C−H activation.

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.

A highly efficient and practical new synthetic strategy for the synthesis of structurally diverse siloles, including the first examples of benzofuran siloles [(XI) and (XII)], is developed.

A highly chemoselective one-pot reaction has been developed involving a tandem semipinacol rearrangement/oxa-Michael addition sequence in which the in situ generated ketol diene intermediate can be transformed specifically to either the spiro- or fused-dihydrofuran products (see scheme). This one-pot tandem reaction represents a general synthetic methodology for the syntheses of the two different kinds of furan derivatives.

The title reaction affords a complex tricyclic system with four continuous stereogenic centers.

Diaryl allylic tertiary alcohols afford up to 93% enantioselectivity by use of a cinchona-derived catalyst and NBS as brominating reagent.

High stereoselectivity in an aqueous medium, the introduction of tri-oxygenated functional groups, and the efficient construction of at least two chiral centers are features of this transformation.

The reaction allows the construction of two adjacent stereocenters: a chiral oxo-quaternary carbon, and a functionalizable halogen.

The formation of the target compounds proceeds via formation of triazoline intermediates and subsequent 1,2-migration.

An efficient first approach to the Stemona alkaloid (±)-Stemonamine has been developed on the basis of a key TiCl4 promoted tandem Semipinacol rearrangement/Schmidt reaction and a Dieckmann condensation reaction.