Heteroarylboronates in rhodium-catalyzed 1,4-addition to enones.

Rhodium(I)-catalyzed 1,4-addition of aryl and alkenylboronic acids to α,β-unsaturated carbonyl compounds is well established, but the transfer of heteroaryl residues in this reaction remains underdeveloped. We have studied heteroaryl MIDA and pinacol boronates as alternatives to the labile boronic acid counterparts. Under racemic conditions, 12 adducts with heteroaryl residues, among them unsubstituted 3- and 4-pyridinyl, 2-furanyl, thienyl, and pyrrolyl groups, were obtained in moderate to excellent yields.

Conformal and highly luminescent monolayers of Alq3 prepared by gas-phase molecular layer deposition.

The gas-phase molecular layer deposition (MLD) of conformal and highly luminescent monolayers of tris(8-hydroxyquinolinato)aluminum (Alq3) is reported. The controlled formation of Alq3 monolayers is achieved for the first time by functionalization of the substrate with amino groups, which serve as initial docking sites for trimethyl aluminum (TMA) molecules binding datively to the amine. Thereby, upon exposure to 8-hydroxyquinoline (8-HQ), the self-limiting formation of highly luminescent Alq3 monolayers is afforded.

Efficient pseudo-enantiomeric carbohydrate olefin ligands.

Highly efficient pseudo-enantiomeric olefin ligands were designed from D-glucose and D-galactose. These ligands yield consistently excellent levels of enantioselectivity in Rh(I)-catalyzed 1,4-additions of aryl- and alkenylboronic acids to achiral enones and high diastereoselectivity with chiral substrates. Contrary to established olefin ligands, they are obtained enantiomerically pure via short syntheses without racemic resolution steps, making them a valuable addition to the arsenal of chiral ligands with olefinic donor sites.