کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1198580 964832 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Tetramethylammonium hydroxide (TMAH) thermochemolysis of 2-arylcoumaran lignin model compounds
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Tetramethylammonium hydroxide (TMAH) thermochemolysis of 2-arylcoumaran lignin model compounds
چکیده انگلیسی

Phenolic 2-arylcoumarans 1–6 were used to examine the behaviors of β-5 subunits in lignin during tetramethylammonium hydroxide (TMAH) thermochemolysis. Products were monitored by gas chromatography/mass spectrometry. The process predominantly provided dimeric products with the opened hydrofuran ring. Substituent changes at the γ-position of ring A and at the 5-position of ring B had a large effect on the product compositions. 2-Arylcoumarans 1 and 6 with the γ-CH2OH substituent predominantly gave 2,3,3′,4′-tetramethoxystilbenes involving the elimination of the γ-CH2OH substituent, while 2–5 with the γ-CH3 substituent gave a mixture of 2,3,3′,4′-tetramethoxy-α-methylstilbenes and α-methoxy-α-(3′,4′-dimethoxyphenyl)-β-(2,3-dimethoxyphenyl)propanes. Substituent –CHCHCH3 on ring B remained unaffected. Substituents –CHCHCH2OH and –COOH on ring B produced the corresponding methyl ether and ester, respectively, by methylation. The –CHCHCHO substituent on ring B was converted to the –CHO substituent.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Analytical and Applied Pyrolysis - Volume 86, Issue 1, September 2009, Pages 185–191
نویسندگان
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