ISSN:
0947-3440
Keywords:
Electrophilic addition
;
Tetradehydrodianthracene
;
Solvent effects
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
5,12:6,11-Di[1,2]benzenodibenzo[a,e]cyclooctene (tetrade-hydrodianthracene, TDDA) (1) reacts with halogens to give transannular (anti) 4, 5 and ring-opened (syn) products 6, 7. The product ratio shows a remarkable solvent dependence. Solvents of medium polarity favor anti addition, whereas syn addition is observed both with increasing and decreasing polarity. For instance, chlorine in toluene adds 100% syn, in dichloroethane 56 % anti, and in trifluorethanol again 100% syn. It is concluded that, depending on solvent polarity, three different mechanisms for electrophilic addition are operative.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.1995199507170
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