Vanillin from Lignin Materials

Abstract

A solution of 100 mg. of the ketone in 5 cc. of benzene was treated with excess methylmagnesium iodide and allowed to stand for twelve hours at room temperature. After hydrolysis and extraction of the product with benzene, the carbinol was crystallized from benzene-petroleum ether giving a total of 100 mg. (93%) of material melting at 118.5-119.5°. Another recrystallization of the compound raised this m. p. to 119-119.5°.(B) From XXII.-When 100 mg. of the ester XXII was refluxed in benzene solution for four hours with excess methylmagnesium iodide and the carbinol isolated as before, there was obtained a total of 95 mg. (95%); m. p. 119-120°.Recrystallization from benzene-petroleum ether gave material melting at 119.5-120°; when mixed with the carbinol prepared in (A) this product melted at 119-120°. Both samples gave dark brown crystals with sulfuric acid with but little color in the liquid.Anal. Caled, for Ci8H,80: C, 86.4; H, 7.2. Found:C, 86.6; , 7.0.l-(2z-Phenanthryl)-propanol-2.-Reduction of 0.5 g. of the ketone XX with 10 cc. of a M solution of aluminum isopropoxide in isopropyl alcohol according to the method of Lund88 gave 0.44 g. (88%) of the secondary alcohol; m. p. 105-107 °. Another recrystallization of the compound from (26) Lund, Ber., 70, 1520 (1937.benzene-petroleum ether raised the m. p. to 107-107.5°.

Recovery of vanillin from Kraft lignin oxidation by ion-exchange with neutralization

“…Borregaard is one of the world's largest producers of vanillin, supplying vanillin from two different processes: one based on guaiacol route and another is based on oxidation of lignosulfonates (sulfite spent liquor) [15]. The presence of vanillin in the alkaline oxidation products of sulfite waste liquor is of theoretical interest from the point of view of lignin chemistry [17]. It has been well known since 1920s that lignin heated under reflux conditions for long times in the presence of active alkali produces a maximum yield of vanillin [18].…”

Efficient biomass pretreatment using ionic liquids derived from lignin and hemicellulose

“…Depending on the methods used, it is possible to direct depolymerization toward desired product streams, such as aromatic aldehydes, acids, and alcohols (33)(34)(35). For example, classic oxidative methods involving CuSO 4 with NaOH yield hydroxyl-and methoxylsubstituted aromatic aldehydes (36), particularly vanillin and syringaldehyde. A similar catalytic system, using CuSO 4 with quaternary ammonium and imidazolium dimethylphosphate ILs, has been shown to convert ∼30% of lignin to aldehydes (37).…”

An integrated process to produce vanillin and lignin-based polyurethanes from Kraft lignin

“…Some other oxidation products can be acetovanillone, dehydrodivanillin, guaiacol, p-hydroxybenzaldehyde, and aromatic acids (Pearl, 1942). have shown, using HPLC and GC analyses, that after chemical oxidation of pine Kraft lignin with molecular oxygen the lignin molecule is degraded producing vanillin and, in some cases, acetovanillone (only under strong oxidation conditions).…”