In the title compound, C(24)H(29)ClO(8)·2.5H(2)O, which contains two organic mol-ecules (A and B) and five heavily disordered water mol-ecules in the asymmetric unit, the γ-lactone ring and the cyclo-hexenone ring are both trans-fused to the central cyclo-decene ring. The cyclehexenone ring features an α,β-unsaturated ketone with torsion angles between the conjugated carbonyl and alkene bonds o...

The bromination of a series of cyclohexenyl substituted secondary amines 1a-i has been investigated using Br2, PHT and NBS. In the case of Br2 and NBS the secondary amines preferentially undergo N-bromination. In contrast, PHT cleanly affords the products of alkene dibromination. In the case ofBr2 the N-bromo species then give the products of alkene dibromination, albeit less efficiently. On su...

Alkylgold(I) complexes were formed from the gold(I)-promoted intramolecular addition of various amine nucleophiles to alkenes. These experiments provide the first direct experimental evidence for the elementary step of gold-promoted nucleophilic addition to an alkene. Deuterium-labeling studies and X-ray crystal structures provide support for a mechanism involving anti-addition of the nucleophi...

The catalytic, enantioselective, cyclization of phenols with electrophilic sulfenophthalimides onto isolated or conjugated alkenes affords 2,3-disubstituted benzopyrans and benzoxepins. The reaction is catalyzed by a BINAM-based phosphoramide Lewis base catalyst which assists in the highly enantioselective formation of a thiiranium ion intermediate. The influence of nucleophile electron density...

An optical fiber has been developed with a maneuverable mini-probe tip that sparges O(2) gas and photodetaches pheophorbide (sensitizer) molecules. Singlet oxygen is produced at the probe tip surface which reacts with an alkene spacer group releasing sensitizer upon fragmentation of a dioxetane intermediate. Optimal sensitizer photorelease occurred when the probe tip was loaded with 60 nmol sen...

Saturated oxygen heterocycles, such as tetrahydrofurans and dihydrobenzofurans, are important motifs in a myriad of biologically active compounds, including natural products and pharmaceutical targets. Therefore, there has been considerable interest in the development of new synthetic methods for the construction of these important structures. Many traditional approaches to the generation of th...

Light alkanes and alkenes are abundant but are underutilized as energy carriers because of their high volatility and low energy density. A tandem catalytic approach for the coupling of alkanes and alkenes has been developed in order to upgrade these light hydrocarbons into heavier fuel molecules. This process involves alkane dehydrogenation by a pincer-ligated iridium complex and alkene dimeriz...

The oxidative cleavage of alkenes is classically performed by chemical methods, although they display several drawbacks. Ozonolysis requires harsh conditions (-78°C, for a safe process) and reducing reagents in a molar amount, whereas the use of poisonous heavy metals such as Cr, Os, or Ru as catalysts is additionally plagued by low yield and selectivity. Conversely, heme and nonheme enzymes ca...