Lignin-Derived Advanced Carbon Materials.

Lignin is a highly abundant source of renewable carbon that can be considered as a valuable sustainable source of biobased materials. By applying specific pretreatments and manufacturing methods, lignin can be converted into a variety of value-added carbon materials. However, the physical and chemical heterogeneities of lignin complicate its use as a feedstock. Herein lignin manufacturing process, the effects of pretreatments and manufacturing methods on the properties of product lignin, and structure-property relationships in various applications of lignin-derived carbon materials, such as carbon fibers, carbon mats, activated carbons, carbon films, and templated carbon, are discussed.

Sulfonic acid resin-catalyzed addition of phenols, carboxylic acids, and water to olefins: Model reactions for catalytic upgrading of bio-oil.

Acid-catalyzed 1-octene reactions with phenol and mixtures of phenol with water, acetic acid and 1-butanol were studied as partial bio-oil upgrading models. Bio-oil from fast biomass pyrolysis has poor fuel properties due to the presence of substantial amounts of water, carboxylic acid, phenolic derivatives and other hydroxyl-containing compounds. Additions across olefins offer a route to simultaneously lower water content and acidity while increasing hydrophobicity, stability and heating value. Amberlyst15, Dowex50WX2 and Dowex50WX4 effectively catalyzed phenol O- and C-alkylation from 65 to 120 degrees C, giving high O-alkylation selectivities in the presence of water, acetic acid and 1-butanol. Octanols and dioctyl ethers were formed from water and octyl acetates and phenol acetates from acetic acid. Phenol alkylation slowed in the presence of water. Dowex50WX2 and Dowex50WX4 were more stable in the presence of water than Amberlyst15 and were successfully recycled. Adding 1-butanol to phenol/water/1-octene, gave emulsion-like mixtures which improved phenol conversion and olefin hydration.

Tandem reactions of 1,3-diacid chlorides with 2-methylimidazoline and 2-methyl-1,4,5,6-tetrahydropyrimidine: one-pot synthesis of 1,8-naphthyridinetetraones.

The reactions of 2-methylimidazoline and 2-methyl-1,4,5,6-tetrahydropyrimidine with 1,3-diacid chlorides, in the presence of Et3N in refluxing MeCN give highly functionalized potentially bioactive 1,8-naphthyridinetetraones. 2-Methylimidazoline and 2-methyl-1,4,5,6-tetrahydropyrimidine can be viewed as tridentate nucleophiles which give four consecutive tandem nucleophilic attacks on electrophiles.