ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Pentacyclo[6. 4. 02, 4. 03, 10. 07, 9]dodeca-5, 11-diene(4) is proposed as new potential precursor of the truncated tetrahedrane 1. The synthesis of several new pentacyclo[5. 4. 0. 02, 4. 03, 9. 06, 8] undec-10-ene (4, 5-homosnoutene) derivatives including homosnouten-5-one(10), 5-methylidenehomosnoutene(19a) as well as homosnoutene-5-carb-aldehyde(17b) and their reactions directed toward ring enlargement to the skeleton of 4 are reported. Although all the homosnoutenes resisted ring expansions, several unexpected new polycyclic systems were obtained. Any intermediate developing a cationic center at C(5) of the skeleton of 10 rearranged with release of strain and opening of one or both three-membered rings to give compounds such as 22 and 23. The aminomethyl derivatives 13a and 13b, upon diazotation, underwent a remarkable fragmentation to give 10 and homosnouten-5-o1(20), respectively. The 5-(dibromomethyl) homosnouten-5-o1(14), upon treatement with t-BuLi, rearranged to the pentacyclic ether 15, while the carbine 11b, generated by the thermal or photochemical decomposition of the tosylhydrazone salt of 17c, solely gave 19a by C, H insertion. The 1, 1-dicyclopropylethene unit in 19c was excited selectively upon irradiation, but the products 26 and 27 of this photochemical rearrangement were derived only from n-participation in diradical intermediates 25a-25c.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19900730506
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