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Updated: May 7, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
Theobrominium perchlorate dibenzo-18-crown-6 3.25-hydrate
Vladislav Kulikov1, Gerd Meyer
1Institut für Anorganische Chemie, Universität zu Köln, Greinstrasse 6, D-50939 Köln, Germany.
Abstract:
The co-crystal, C7H9N4O2 (+)·ClO4 (-)·C20H24O6·3.25H2O, consists of theobrominium (3,7-di-methyl-2,6-dioxo-1H-purin-9-ium) cations, perchlorate anions and dibenzo-18-crown-6 and water mol-ecules. The crown ether is in a bent conformation, in which the planes of the aromatic rings subtend an angle of 63.7 (1)°. Inter-molecular O-H⋯O hydrogen bonding between the water mol-ecules and the O atoms of the cyclic ether delimit an empty space reminiscent of a hollow cage. The water mol-ecules are additionally linked to the cations by N-H⋯O hydrogen bonding. One of the positions of the water molecules is occupied only fractionally (25%) and is located outside this framework.
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