15,16‐Dioxo‐syn‐1,6:8,13‐bismethano[14]annulen

Abstract

len von [ M~~( O~C R )~] -K o m p l e x e n besetzt meist ein Sauerstoffatom des Nachbarmolekuls diese Position [']. Dafur spricht auch, darj rnit chiralen Sauren wie Phenylalanin in CFICOzH praktisch kein C D gemessen werden konnte. Abb. I . CD-Spektren von Alkyl(pheny1)thiophosphinsauren [(R)-und (S)-Form], von (R)-tert-Butyl(pheny1)selenophosphinsaure und von Thiophosphorsaure-methyl-a-naphthylester in CF3COIH.

Annulenes, 1980–2000

“…Other related 1,6:8,13-bridged [14]annulenes include the syn and anti dicarbonyl bridged compounds 70 and 71. 113,114 Either of these compounds might be expected to decompose readily to give the stable products anthracene and carbon monoxide, but the syn-isomer 70 is very stable and resists flash vacuum pyrolysis at 500 ЊC. X-Ray structures show that the periphery of 70 is virtually planar, despite repulsion between the two adjacent carbonyl groups.…”