The zirconocene-catalyzed sequential ethylcarboxylation of alkenes using ethylmagnesium chloride and carbon dioxide has been developed. A range of alkenes were transformed into the corresponding carboxylic acids in high yields.

The cuticular lipids of the cavity-nesting adult female solitary bees, Osmia lignaria Say and Megachile rotundata (F.) (Hymenoptera: Megachilidae), were analyzed by gas chromatography (GC) and combined GC-mass spectrometry. The cuticular lipids of these female bees are mainly consisted of hydrocarbons. For O. lignaria, nearly 64% of the cuticular lipids were C(25)-C(31) mono-alkenes. For M. rot...

Supported gold nanoparticles catalyze the semihydrogenation of alkynes to alkenes with ammonia borane or amine borane complexes in excellent yields and under mild conditions. Internal alkynes provide cis-alkenes, making this protocol an attractive alternative of the classical Lindlar's hydrogenation.

A stereoselective hypervalent iodine-promoted oxidative rearrangement of 1,1-disubstituted alkenes has been developed. This practically simple protocol provides access to enantioenriched α-arylated ketones without the use of transition metals from readily accessible alkenes.

Catalytic reductive coupling processes have been developed in numerous contexts as a strategy for the regioand stereoselective installation of alkenes. The direct coupling of a polar p system with a relatively nonpolar p system is often a successful strategy for selectively accomplishing synthetically desirable heterocouplings while avoiding undesired homocoupling of either reagent. For example...

Abstract ?-Alkenes (terminal alkenes) are important fuel and platform chemicals that mainly produced from petroleum. Microbial synthesis might provide a sustainable approach for ?-alkenes. In this work, we engineered the methylotrophic yeast Pichia pastoris to produce long-chain (C15:1, C17:1 C17:2) ?-alkenes via decarboxylation of fatty acids. Combinatorial engineering, including enzyme select...

Hypervalent iodine(III)-mediated dioxygenation and diamination of alkenes have been previously developed. In this study, the potential application of hypervalent iodine(III) reagent was successfully extended to the dialkylation and cyclopropa(e)nation of unsaturated alkenes and alkynes. The reactions of alkenes with malononitrile and other active methylene compounds as the carbon nucleophiles g...

In social insect colonies, recognition of nestmates, kinship, caste and reproductive status is crucial both for individuals and for the colony. The recognition cues used are thought to be chemical, with the hydrocarbons found on the cuticle of insects often cited as being particularly important. However, in honeybees (Apis mellifera) the role of cuticular hydrocarbons in nestmate recognition is...

We have developed a novel and simple protocol for the direct incorporation of a difluoromethyl (CF2 H) group into alkenes by visible-light-driven photoredox catalysis. The use of fac-[Ir(ppy)3] (ppy=2-pyridylphenyl) photocatalyst and shelf-stable Hu's reagent, N-tosyl-S-difluoromethyl-S-phenylsulfoximine, as a CF2 H source is the key to success. The well-designed photoredox system achieves synt...

Dioxoruthenium(VI) porphyrins including those containing chiral porphyrinato ligands can be readily prepared by oxidation of [RuII(Por)(CO)(MeOH)] with PhIO or metachloroperoxybenzoic acid. Similar reactions with PhINTs gave [Ru(Por)(NTs)2] isolated as air stable solids at room temperature. The [Ru(Por)O2] complexes are competent oxidants for epoxidation of alkenes with high selectivities. Enan...