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MO investigations on lignin model compounds VIII. A PCILO study of intramolecular hydrogen bond in guaiacol and o-vanillin

✍ Scribed by Milan Remko

Publisher: Elsevier Science
Year: 1979
Weight: 286 KB
Volume: 14
Category: Article
ISSN: 0378-4487
DOI: 10.1016/0378-4487(79)80015-1

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✦ Synopsis

The semiempirical PCILO method has been used to study stereochemistry of the intramolecular hydrogen bond O-H...0 in 2-methoxyphenol (guaiacol) and 2-methoxy-6-fonmyl phenol (o-vanillin). According to my calculations, the hydrogen bond in guaiacol is weak and has energy of 2.7 kJ/mole and forms a planar five membered ring. The hydrogen bond fonmed by carbonyl oxygen of the formyl gTOUp in o-vanillin is more stable and fonms a nonplanar six membered ring with an angle of rotation of the -CHO group out-of-the-plane of the benzene ring equal to 15O. The energy of this hydrogen bond is 6.07 kJ/mole.

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