
TY  - JOUR
A1  - Paddon-Row, MN 
A1  - Patney, HK 
A1  - Pasupuleti, LN 
T1  - An improved approach to benzene annelation: the synthesis of 11-substituted octahydro-1,4:9,10-dimethanoanthracenes and a study of OH&#8230;p bonding in these systems
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1982
VL  - 35
IS  - 2
SP  - 307
EP  - 317
KW  - 
UR  - https://doi.org/10.1071/CH9820307 
N2  - A procedure for benzene annelation, which incorporates the best features of previously reported techniques, is described and is applied to the synthesis of a series of 11-substituted octahydro-1,4:9,10-dimethanoanthracenes (1a-e). Thus addition of 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene(7) to (1&#946;,4&#946;, 4a&#945;, 5&#945;, 8&#945;, 8a&#945;)-anti-9-acetoxy-1,2,3,4,4a,5,8,8a-octahydro-1,4:5,8-dimethanonaphthalene(4b) gave the adduct (8b).* Deacetalization of (8b) followed by thermal, cheletropic loss of CO and subsequent base-induced dehydrochlorination gave the 5,6,8-trichlorooctahydro-1,4:9,10-dimethanoanthracen-anti-11-ol (17b) which could easily be converted into (1c) by using sodium and ethanol. Infrared and 1H n.m.r. studies revealed the presence of a strong intramolecular OH&#8230;&#960; bond in the syn-alcohol (1e). The observation of an unusually large vicinal coupling constant, J(HCOH) 12 Hz, for (1e) implies that the H-C-O-H exists in the antiperiplanar conformation which also maximizes the strength of the OH&#8230;&#960; bond. 
ER  -

