76429-74-8Relevant academic research and scientific papers
Relevance of Conformational Constraints to the Regioselective Lithiation of Aromatic Diethers. Application to the Convenient Construction of the DEF Tricyclic Subunit of the Austalides
Paquette, Leo A.,Schulze, Matthias M.,Bolin, David G.
, p. 2043 - 2051 (2007/10/02)
The lithiation of 29 and 30 is shown to occur at all three sites with a dissimilar kinetic preference.For the dihydrofuran, reaction at the proton labeled Hβ' operates predominantly; in the dihydropyran example, Hα is the favored sit
Oxygen Heterocycles by the Parham Cyclialkylation
Bradsher, Charles K.,Reames, David C.
, p. 1384 - 1388 (2007/10/02)
The addition of butyllithium at -100 deg C to ω-bromoalkyl ethers of o-bromophenol (and its congeners) led to preferential exchange of the aryl bromine at position 2.The resulting organolithium reagents, under suitable conditions, cyclized to afford 2,3-dihydrobenzofurans (6), 3,4-dihydro-2H-1-benzopyrans (13), or 2,3,4,5-tetrahydro-1-benzoxepins (16) in good yields, but less satisfactory results were obtained with the intermediate expected to produce 8-methyl-3,4,5,6-tetrahydro-2H-1-benzoxocin (19). ω-Bromoethyl and ω-bromopropyl ethers of suitable dibromophenols were treated successively with 2 equiv of butyllithium and an electrophile to yield derivatives of 6 and 13.
