Stereochemistry of Reactions Involving Rotationally Restricted, Sterically Hindered Cations, Radicals, and Anions: 9-Fluorenyl Systems

Journal of Organic Chemistry

Volumn 69, Issue 4, 2004, Pages 1186-1195

  Hou, Yuqing ^a   Meyers, Cal Y ^a  

^a SOUTHERN ILLINOIS UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

FREE RADICALS; NEGATIVE IONS; OLEFINS; POSITIVE IONS; THERMODYNAMICS;

ENANTIOMERS; STERICALLY HINDERED CATIONS;

STEREOCHEMISTRY;

9 (O TERT BUTYLPHENYL) 2 METHYLFLUORENE; 9 (O TERT BUTYLPHENYL) 9 METHOXY 2 METHYLFLUORENE; 9 (O TERT BUTYLPHENYL)FLUORENE; ANION; CATION; FLUORENE DERIVATIVE; RADICAL; UNCLASSIFIED DRUG;

ACIDIFICATION; ANALYTICAL ERROR; ARTICLE; CHIRALITY; CRYSTAL STRUCTURE; ELECTRON; ENANTIOMER; ENERGY; REACTION ANALYSIS; STEREOCHEMISTRY; STEREOSPECIFICITY;

EID: 1242329887     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo0351015     Document Type: Article

References (55)

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50. 3 likewise produced this coloration. Moreover, formation of the free-radical intermediate in the latter transformation was verified by the isolation of its air-oxidation product, ap-9-(o-isopropylphenyl)-9-fluorenyl peroxide, which was unequivocally characterized by X-ray analysis. Under the same conditions, the corresponding peroxide from radical 14 was not observed, most likely for steric reasons.
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54. a of 1 by the standard method, using 4-chloro-2-nitroaniline as indicator, required a full day to get a stable reading: Meyers, C. Y.; Hou, Y.; Lutfi, H. G.; Robinson, P. D. Abstracts of Papers; 210th National Meeting of the American Chemical Society, Chicago, IL, Aug 20-24, 1995; American Chemical Society: Washington, DC, 1995; ORGN 297.
55. 3OD, but 100% as the sp rotamer in the crystalline state, and 9-(m-tert-butylphenyl)-fluorene rotates rapidly in solution showing no conformational preference, but crystallizes as its ap rotamer exclusively.