Premium
Synthese und 1 H‐NMR‐Analyse von Triafulvalen‐Vorstufen
Author(s) -
Huwyler Rolf,
Li Xiaoming,
Bönzli Peter,
Neuenschwander Markus
Publication year - 1999
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/(sici)1522-2675(19990804)82:8<1242::aid-hlca1242>3.0.co;2-8
Subject(s) - chemistry , stereochemistry
Synthesis and 1 H‐NMR Analysis of Triafulvalene Precursors . An attractive concept for the synthesis of triafulvalene ( 1 ) by retro‐Diels‐Alder reaction ( RDA reaction) of precursors 4 and 5 is presented. Both precursors are available in two steps by dibromocarbene addition to dibenzobarrelene ( 8 → 9 ) and barrelene ( 10 → 11 ), followed by CuCl 2 ‐induced formal `carbene dimerization' ( 9 → 4 and 11 → 5 , respectively). Thermal‐fragmentation experiments of triafulvalene precursor 4 were unsuccessful, mainly due to the very low volatility of 4 . Spectral parameters of the complex 1 H‐NMR spectrum of 3,3′‐bi(tricyclo[3,2,2,0 2,4 ]nona‐6,8‐dienylidene) ( 5 ) have been determined by analysis of subspectra generated by selective H,H‐decoupling experiments followed by iteration/simulation sequences.