13133-97-6Relevant academic research and scientific papers
Reductive lithiation of cyclic benzofused ethers: A source of oxygen-functionalised organolithium compounds
Yus, Miguel,Foubelo, Francisco,Ferrández, José V,Bachki, Abderrazak
, p. 4907 - 4915 (2007/10/03)
The reaction of 2,3-dihydrobenzofuran (1) with lithium and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB, 5%) in THF at 0°C for 1.5h, followed by addition of an electrophile [E+=H2O, tBuCHO, PhCH2CHO, Ph(CH2)2CHO, PhCHO, furfural, Me2CO, Et2CO, cyclopentanone, cyclohexanone, cyclooctanone, (-)-menthone] in THF at -78°C gives, after hydrolysis, compounds 3. Some diols 3 are easily transformed into 2-substituted chromans 6 under acidic reaction conditions. The reductive lithiation of chroman (7) at 20°C for 3h leads exclusively to the intermediate 8, which is formed through a dearylation process, and isomerises to the apparently more stable benzylic intermediate 9. The reaction of these intermediates with different electrophiles {E+=tBuCHO, PhCHO, furfural, Me2CO, [CH3(CH2)4]2CO, cyclopentanone, cyclohexanone, (-)-menthone, Ph2CO}, at -78°C in THF leads, after hydrolysis, to a mixture of regioisomers 10 and 11. The reaction of 2,3-benzofuran (12) with an excess of lithium and a catalytic amount of DTBB (5%) in THF at 0°C for 45min leads to dianionic intermediate 13 through a dealkylation process, which after hydrolysis gives 2-vinylphenol 14. In the case of 4H-chromene (15), reductive opening is performed at 20°C for 45min, a mixture of dearylation and dealkylation intermediates 16 and 17, respectively, is obtained (2:1 ratio) giving, after hydrolysis, 3-phenylpropanal (18) and 2-allylphenol (19).
Generation of γ-oxy-substituted benzylithium derivatives by reductive lithiation of 4-phenyl-1,3-dioxanes
Azzena, Ugo,Pilo, Luciano
, p. 664 - 668 (2007/10/03)
Reductive cleavage of 1,3-dioxanes 1a-c with Li metal in the presence of a catalytic amount of naphthalene in THF, followed by reaction with different electrophiles, allowed the synthesis of 3-substituted- and 3,3-disubstituted- 3-phenylpropan-1-ols 4 in good yields.
Reductive Rearrangement of 4-Phenyl-1,3-dioxans to 2-Phenylbutane-1,4-diols upon Treatment with Sodium-Potassium Alloy
Bailey, William F.,Cioffi, Eugene A.
, p. 155 - 156 (2007/10/02)
Reduction of 4-phenyl-1,3-dioxan with Na-K alloy affords 2-phenylbutane-1,4-diol as the major product along with smaller amounts of 3-phenylpropan-1-ol and 3,4-diphenylhexane-1,6-diols.
