Carbenes in polycyclic systems: generation and fate of potential adamantane‐1,3‐dicarbenes

• Published in: Journal of physical organic chemistry Vol. 21; no. 4; pp. 299 - 305
• Main Authors: Klaić, Lada, Alešković, Marija, Veljković, Jelena, Mlinarić‐Majerski, Kata
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.04.2008
• Subjects: adamantane; azines; carbenes; dicarbenes; polycyclic compounds
• ISSN: 0894-3230; 1099-1395
• DOI: 10.1002/poc.1319

Potential formation and reactions of adamantane‐1,3‐dicarbenes 1–3 generated under different conditions and from different precursors, such as sodium salt of adamantane‐1,3‐dicarbaldehyde ditosylhydrazone (4a), sodium salt of 1,3‐diacetyladamantane ditosylhydrazone (5a), sodium salt of 1,3‐dibenzoyladamantane ditosylhydrazone (6a), and 1,3‐bis(diazobenzyl)adamantane (7) are reported. Carbene species generated thermally from 4a yielded bishomoadamantane (15), as a final product, via intramolecular insertion into adjacent CC bond and formation of putative anti‐Bredt olefin species, followed by hydrogen ion. Pyrolysis of the same sodium salt 4a in the presence of hydrogen donor n‐Bu3SnH afforded 1,3‐dimethyladamantane (17). Thermal decomposition of sodium salt 5a afforded 1,3‐divinyladamantane (14). However, thermal decomposition of sodium salt 6a and diazo‐precursor 7 gave benzonitrile as a sole identified product. On the contrary, photolysis of 7 afforded dimeric azine 21. Finally, the synthetic pathways of novel tosylhydrazone derivatives 4, 5, 6 and their corresponding sodium salts, as well as bis‐diazocompound 7 are described. Copyright © 2008 John Wiley & Sons, Ltd. Potential formation and reactions of adamantane‐1,3‐dicarbenes 1–3 generated under different conditions and from different precursors are reported. All of the products can be rationalized by sequential reactions of monocarbenes as well as by reactions of dicarbene species.