Room-Temperature Asymmetric Transfer Hydrogenation of Biomass-Derived Levulinic Acid to Optically Pure γ-Valerolactone Using a Ruthenium Catalyst.

This study presents a first report on ruthenium-catalyzed asymmetric transfer hydrogenation (ATH) of levulinic acid (LA) to chiral γ-valerolactone (GVL). ATH of LA has been explored with Noyori's chiral catalyst (Ru-TsDPEN) in methanol solvent. Efficacy of ATH reaction of LA was investigated under different reactions conditions such as temperature, catalyst, and hydrogen donor concentration.

Highly Enantioselective One-Pot Synthesis of Chiral β-Heterosubstituted Alcohols via Ruthenium-Prolinamide-Catalyzed Asymmetric Transfer Hydrogenation.

The utility of a chiral Ru-prolinamide catalytic system has been demonstrated in one-pot synthesis of optically active β-triazolylethanol and β-hydroxy sulfone derivatives. The said methodology proceeds through asymmetric transfer hydrogenation of in situ formed ketones of the corresponding chiral products. Various chiral prolinamide ligands were screened, and ligand with isopropyl groups substituted at the ortho position has shown excellent activity at 60 °C in aqueous medium producing up to 95% yield and 99.

Recent Advances Utilized in the Recycling of Homogeneous Catalysis.

Homogeneous catalysts often show high activity and selectivity towards the various chemical transformations. Most of the transition metal-based active catalysts are expensive, rare, and have strict regulations for their use in pharmaceutical products. Hence, there is a requirement to develop suitable technologies for the practical separation and recycling of metal complex catalysts along with the sustainability of the process.

Morphometric significance of maxillary arch in sexual dimorphism in North Indian population.

Background: Tooth is the hardest and chemically (except mineral contents) the most stable structure in the body, which makes teeth as the first-rate material for genetic and forensic investigations. Sex determination of skeletal remains forms an important part of archaeological and medicolegal examinations. Hence, the aim of the present study was to analyse the morphometric and dimensional variation between male and female in north Indian population using maxillary arch parameters.

Asymmetric Transfer Hydrogenation of Imines in Water by Varying the Ratio of Formic Acid to Triethylamine.

Asymmetric transfer hydrogenation (ATH) of imines has been performed with variation in formic acid (F) and triethylamine (T) molar ratios in water. The F/T ratio is shown to affect both the reduction rate and enantioselectivity, with the optimum ratio being 1.1 in the ATH of imines with the Rh-(1S,2S)-TsDPEN catalyst.

Estimation and correlative study of salivary nitrate and nitrite in tobacco related oral squamous carcinoma and submucous fibrosis.

Unlabelled: Oral cancer is one of the ten leading cancers of the world. In India, it is one of the common cancers and is an important public health problem. Tobacco plays significant role in etiology of oral squamous carcinoma.