Synthesis and Physical Properties of Sterically Congested Cycloalkenes, 1,2-Di-tert-butyl-3,3,5,5-tetramethylcyclopentene and 1,2-Di-tert-butyl-3,3,6,6-tetramethylcyclohexene

Autor:	Chie Tsuchiya, Takahiro Shimada, Akihiko Ishii, Ken Furusawa, Juzo Nakayama, and Takenori Omata
Rok vydání:	2000
Předmět:	Steric effects Tert butyl chemistry.chemical_compound chemistry Bicyclic molecule Yield (chemistry) Organic Chemistry Organic chemistry Dimethyldioxirane Trioxide Medicinal chemistry Isomerization Derivative (chemistry)
Zdroj:	The Journal of Organic Chemistry. 65:1799-1806
ISSN:	1520-6904 0022-3263
DOI:	10.1021/jo991760z
Popis:	Two sterically congested cycloalkenes (9 and 10), congeners of tetra-tert-butylethylene, were synthesized and characterized. Oxidation of the bicyclic 1,3-dithietane 8 with dimethyldioxirane (DMD) gave the endo,endo-disulfoxide 13, thermal isomerization of which to the endo,exo-disulfoxide 15 followed by oxidation with DMD gave the trioxide 18. Heating 18 in refluxing 1,3-dimethyl-2-imidazolidinone furnished 1,2-di-tert-butyl-3,3,5,5-tetramethylcyclopentene (9) in 69% yield by a 2-fold extrusion process. The reaction of the 1,6-diketone dihydrazone 23 with Se(2)Cl(2) gave the selenadiazoline 34 and the 1,3-diselenetane 35. Heating 34 at 115-130 degrees C gave 1,2-di-tert-butyl-3,3,6,6-tetramethylcyclohexene (10), a "didehydro" derivative of tetra-tert-butylethylene, in 43% yield. The C=C bond in 10 is strained in degree comparable to those of most strained alkenes reported so far.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f053ddec6cc3962050d12a38e3dd2662 https://doi.org/10.1021/jo991760z Zobrazit plný text záznamu