1,8a-Dihydroindolizines as Components of Novel Photochromic Systems

✍ Scribed by Dipl.-Chem. G. Hauck; Prof. Dr. H. Dürr

• Publisher: John Wiley and Sons
• Year: 1979
• Tongue: English
• Weight: 224 KB
• Volume: 18
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.197909451

✦ Synopsis

fluorine atoms are brought closer together (see Fig. 2). The distance between the axial fluorine atoms and the hydrogen atoms is only 240 pm; however, no evidence of H...F bridges is apparent from the spectroscopic data.

The SCF geometrical optimization shows that the isomer with an equatorially oriented CH2 group is unstable, and that a high torsional barrier exists, with an estimated value of 77 k ~a l / m o l [ ~~.

In spite of its thermal stability, H2C=SF4 is very reactive. Reactions with halogens or photolysis yield SF4.

Free carbene has not yet been detected as an intermediate in these reactions (however irradiation of diluted diazomethane also yields large amounts of ethylenef8]).

With polar reagents, addition to the C=S bond occurs.