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Title: The Effect of Dicarboxylic Acid Catalyst Structure on Hydrolysis of CelluloseModel Compound D-Cellobiose in Water
Background:Polycarboxylic acids are of interest as simple mimics for cellulase enzyme catalyzed depolymerization of cellulose. In this study, DFT calculations were used to investigate the effect of structure on dicarboxylic acid organo-catalyzed hydrolysis of cellulose model compound D-cellobiose to D-glucose. Methods:Binding energy of the complex formed between D-cellobiose and acid (Ebind), as well as glycosidic oxygen to dicarboxylic acid closest acidic H distance were studied as key parameters affecting the turn over frequency of hydrolysis in water. Result:α-D-cellobiose - dicarboxylic acid catalyst down face approach showed high Ebind values for five of the six acids studied; indicating the favorability of down face approach. Maleic, cis-1,2-cyclohexane dicarboxylic, and phthalic acids with the highest catalytic activities showed glycosidic oxygen to dicarboxylic acid acidic H distances 3.5-3.6 Å in the preferred configuration. Conclusion:The high catalytic activities of these acids may be due to the rigid structure, where acid groups are held in a fixed geometry.  more » « less
Award ID(s):
1704144
PAR ID:
10483283
Author(s) / Creator(s):
;
Publisher / Repository:
ACS
Date Published:
Journal Name:
Current Organocatalysis
Volume:
9
Issue:
2
ISSN:
2213-3372
Page Range / eLocation ID:
163 to 171
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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