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Charge-assisted encapsulation of two chlorides by a hexaprotonated azamacrocycle.

ABSTRACT: A chloride complex of a hexaprotonated azamacrocycle has been isolated, and its structure has been determined by X-ray crystallography showing two encapsulated chloride anions in the cavity. The two internal guests are coordinated at two binding sites on the opposite side of the macrocycle through trigonal recognition by hydrogen-bonding interactions. The other four chlorides are located outside the cavity, each with a single hydrogen bond from secondary amines. Ab initio calculations based on density functional theory (DFT) suggest that the encapsulation of two chlorides inside the cavity leads to a significant charge transfer from the anions to the protonated amines.

SUBMITTER: Hossain MA

PROVIDER: S-EPMC2873200 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Charge-assisted encapsulation of two chlorides by a hexaprotonated azamacrocycle.

Hossain Md Alamgir MA Saeed Musabbir A MA Fronczek Frank R FR Wong Bryan M BM Dey Kalpana R KR Mendy John S JS Gibson Don D

Crystal growth & design 20100301 4

A chloride complex of a hexaprotonated azamacrocycle has been isolated, and its structure has been determined by X-ray crystallography showing two encapsulated chloride anions in the cavity. The two internal guests are coordinated at two binding sites on the opposite side of the macrocycle through trigonal recognition by hydrogen-bonding interactions. The other four chlorides are located outside the cavity, each with a single hydrogen bond from secondary amines. Ab initio calculations based on d ...[more]

PMID: 20495667

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