1,3-Dipolar Cycloreversion of 1-Azetines
✍ Scribed by Priv.-Doz. Dr. Klaus Burger; Dipl.-Chem. Willy Thenn; Evi Müller
- Publisher
- John Wiley and Sons
- Year
- 1973
- Tongue
- English
- Weight
- 99 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0044-8249
No coin nor oath required. For personal study only.
✦ Synopsis
3 + I]-Cycloaddition of nitrile ylides"' (obtained by thermolysis of 4,5dihydro-1,3,5h5-oxazaphospholes[2') to isocyanides leads to I-azetines ( l ) [ 3 3 4 1 . This reaction is photochemically reversible.
📜 SIMILAR VOLUMES
I,3-Dipolar q&additions ofdiphenylnim%nines with 2&O-and2EtS-temmzethyi-I-azetines (la,b) are accompanied by ring-opening and loss of EtXH (LX = 0 or S) to give 1,2,4-triasoies (3), whereas with N-(4-nitrophenyl) nimXmines the qected cycloadducts andlor ring-opened products are formed.
The cycloaddition of diphenyldiazomethane (8) to 16 thioketones at 40 • C which furnishes tetrasubstituted 2,5-dihydro-1,3,4-thiadiazoles, is followed by rapid N 2 loss (see the preceding paper), with one exception: For the dihydrothiadiazole 10, the N 2 extrusion is slower by a factor of 4900 than
The photoelectron spectrum of 1-azetine has been obtained and is analysed using semi-empirical (MNLX) calculations. The extensive f..z structure of the fust band is explained by large bond-angle differences between the ground states of the neutral molecule and its radical cation.