Premium
Phenanthro‐Annelated [5.5.6.6]‐ and (Broken) [6.5.6]Fenestranes
Author(s) -
Bredenkötter Björn,
Neumann Beate,
Stammler HansGeorg,
Kuck Dietmar
Publication year - 2014
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201301382
Subject(s) - chemistry , cyclohexane , ring (chemistry) , stereochemistry , cis–trans isomerism , nuclear magnetic resonance spectroscopy , medicinal chemistry , organic chemistry
The construction of the polycyclic frameworks of phenanthro‐annelated all ‐ cis ‐[5.5.6.6]fenestrane, cis , cis , trans , cis ‐[5.5.6.6]fenestrane, and a related “broken” [6.5.6]fenestrane is reported for the first time. On the basis of our established synthesis of benzoannelated fenestrindanes, spirocyclic di(9‐phenanthryl)methyl‐1,3‐indanediols were prepared with complete stereocontrol and subjected to cyclodehydration. Surprisingly, the 9‐phenanthrylmethyl residues underwent preferential “ peri ” attack, rather than “ ortho ” attack, to generate 1,10‐phenanthro rather than 9,10‐phenanthro units. In this way, the cyclodehydration of 2,2‐di(9‐phenanthryl)methyl‐1,3‐indanediol gives rise to two new six‐membered rings with the [6.5.6]fenestrane skeleton. The cyclodehydration of the related trans ‐ and cis ‐diphenanthryl spiro(cyclohexane‐1,2′‐indanediols) generated one new five‐ and one new six‐membered ring stereospecifically to afford the respective all ‐ cis ‐ and cis , cis , trans , cis ‐benzodiphenanthro[5.5.6.6]fenestranes in good yields. The crucial constitutional and stereochemical features of the new fenestranes were determined by single‐crystal X‐ray structure analysis and variable‐temperature (VT) NMR spectroscopy.