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Updated: Jun 1, 2026

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
Published on: April 4, 2014
2,2'-Dimethoxy-4,4'-[rel-(2R,3S)-2,3-di-methylbutane-1,4-diyl]diphenol
Abstract:
The title mol-ecule, C(20)H(26)O(4), commonly known as meso-dihydro-guaiaretic acid, is a naturally occurring lignan extracted from Larrea tridentata and other plants. The mol-ecule has a noncrystallographic inversion center situated at the midpoint of the central C-C bond, generating the meso stereoisomer. The central C-C-C-C alkyl chain displays an all-trans conformation, allowing an almost parallel arrangement of the benzene rings, which make a dihedral angle of 5.0 (3)°. Both hydr-oxy groups form weak O-H⋯O-H chains of hydrogen bonds along [100]. The resulting supra-molecular structure is an undulating plane parallel to (010).
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Structure and Nomenclature of Alcohols and Phenols
Alcohols are one of the most important functional groups in organic chemistry. The name of alcohol comes from the hydrocarbon from which it is derived. Alcohols are organic molecules containing the functional hydroxyl or –OH group directly bonded to carbon. Phenols have an OH group directly attached to a benzene ring. While alcohols are colorless, phenol is a white crystalline compound with a characteristic "hospital smell" odor.
As with other organic compounds, alcohols and phenols...
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