ISSN:
0009-2940
Keywords:
Ring-chain equilibria of carbanions and radicals / Cyclobutyl anion, stability of / Endocyclic ring opening of cyclobutyl radicals / Ziegler ether cleavage with lithium and sodium / C-C σ-bond cleavage with lithium metal
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Attempted Rearrangement of Cyclobutyl Anions to 3-Butenyl Anions: Endocyclic Ring Opening upon Reaction of 3.3-Diphenyl-1-vinylcyclobutyl Methyl Ether with Alkali Metals - via Anions or Radicals?The reaction of the title compound 16 with lithium or sodium in THF yields mainly the open-chain E/Z isomeric trianions 31 ⇌ 32 besides the expected cyclobutyl anion 10. The endocyclic ring opening takes place via the radical intermediate 28 primarily yielding a butadiene derivative 29, which is then further reduced. The anion 10 - prepared independently by deprotonation of the corresponding hydrocarbon 18 - does not rearrange. On investigating side reactions it was discovered that 4,4-diphenyl-1-butene derivatives treated with lithium in THF undergo C-C bond cleavage affording diphenyl-methyllithium in good yields.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19901230131
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