The chemical investigation of an ethyl acetate extract (EtOAc) obtained from Laurencia obtusa, collected in Corsica, allowed for the identification of three new compounds (1, 2, and 4) and six known compounds. Compounds 1 to 4 were isolated and fully characterized by a detailed spectroscopic analysis. Compounds 1 and 2 are two C15-acetogenins sharing the same ring system: a tetrahydropyran link...

A high density monolayer of diisocyanide on gold surface was utilized as a platform of supported Rh catalyst for selective 1,4-hydrogenation of α,β-unsaturated carbonyl compounds. The catalyst exhibited high turnover numbers in a range of 50 000 to 150 000 per Rh atom and showed steady catalyst performance over six recycle usages.

Pin the amine on the gamma: A new method has been developed for the γ-addition of nitrogen nucleophiles to γ-substituted alkynoates or allenoates through intra- and intermolecular processes that are catalyzed by spirophosphine 1. An asymmetric version of this reaction affords enantioenriched pyrrolidines, indolines, and γ-amino-α,β-unsaturated carbonyl compounds.

The highly enantioselective dienamine-mediated formation of 5-bromo-6-(trifluoromethyl)-3,4-dihydro-2H-pyrans from α,β-unsaturated aldehydes and α-bromo-(trifluoromethyl)-enones employing a C2-symmetric aminocatalyst is described. The products are demonstrated to be applicable in coupling reactions directly onto the ring, thereby granting access to a broad scope of highly substituted 6-(trifluo...

A new approach to the synthesis of cyclopenta[b]benzofuran derivatives via reaction of 1,3-dicarbonyl compounds with α,β,γ,δ-unsaturated aldehydes is described. The constitution and configuration of the new products have been firmly established by means of residual dipolar couplings (RDCs) and ab initio (13)C NMR chemical shift predictions.

Title High density monolayer of diisocyanide on gold surface as a platform of supported Rh-catalyst for selective 1,4hydrogenation of α,β-unsaturated carbonyl compounds Author(s) Jagtap, Sachin; Kaji, Yoshinori; Fukuoka, Atsushi; Hara, Kenji Citation Chemical Communications, 50: 5046-5048 Issue Date 2014-04 DOI Doc URL http://hdl.handle.net/2115/55274 Right Type article Additional Information F...

Adding a small amount of fully dispersed Pt entities onto the Au surface in Au/SiO(2) catalyst is found to be an efficient approach to improve the catalytic activity of Au (up to 70-fold) for the hydrogenation of α,β-unsaturated carbonyl compounds, without alternating its selectivity towards C=O or C=C bond hydrogenation.

AgOTf-catalyzed one-pot reactions of 2-alkynylbenzaldoximes with various α,β-unsaturated carbonyl compounds under mild conditions are described, which provides a facile and efficient pathway for the synthesis of 1-alkylated isoquinoline derivatives. The method tolerates a wide range of substrates and allows for the preparation of the products of interest in moderate to excellent yields.