1
|
Partial and Total Solvent-Free Limonene’s Hydrogenation: Metals, Supports, Pressure, and Water Effects. J CHEM-NY 2020. [DOI: 10.1155/2020/5946345] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bio-based solvents menthene and menthane were obtained through limonene’s partial and total hydrogenation under various catalytic conditions. Heterogeneous catalysts based on different active metals and supports (carbon, alumina, and silica) were systematically tested for solvent-free total and partial hydrogenation of limonene under high and low hydrogen pressure. Influences of these catalysts on the formation of menthene, menthane, and cymene, a dehydrogenated product, were determined. The impact of water addition on the conversion and selectivity of the catalysts was also investigated. Amongst all tested catalysts, Rh/Alumina which was never tested for total and partial hydrogenation of limonene was the most effective as 1-menthene was quantitatively produced at low pressure (0.275 MPa) while menthane was mostly obtained at a higher pressure (2.75 MPa). Water addition on Rh/Alumina favoured menthene production even at high pressure. To propose menthane, menthene, and menthane/menthene mixture as an alternative to fossil-based solvents such as n-hexane for the extraction of natural products, β-carotene, vanillin, and rosmarinic acid solubilizations have been investigated. If a modeling approach using COSMO-RS software predicted a comparable solubilization of these 3 compounds for the 3 solvents, experimental assays revealed that menthene solubilizes β-carotene, vanillin, and rosmarinic acid three to five times better than n-hexane.
Collapse
|
2
|
Prasanna R, Guha S, Sekar G. Proton-Coupled Electron Transfer: Transition-Metal-Free Selective Reduction of Chalcones and Alkynes Using Xanthate/Formic Acid. Org Lett 2019; 21:2650-2653. [DOI: 10.1021/acs.orglett.9b00635] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ramanathan Prasanna
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
| | - Somraj Guha
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
| | - Govindasamy Sekar
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
| |
Collapse
|