3214-36-6Relevant academic research and scientific papers
Catalytic Asymmetric Synthesis of Cyclohexanes by Hydrogen Borrowing Annulations
Armstrong, Roly J.,Akhtar, Wasim M.,Young, Tom A.,Duarte, Fernanda,Donohoe, Timothy J.
supporting information, p. 12558 - 12562 (2019/08/16)
Hydrogen borrowing catalysis serves as a powerful alternative to enolate alkylation, enabling the direct coupling of ketones with unactivated alcohols. However, to date, methods that enable control over the absolute stereochemical outcome of such a process have remained elusive. Here we report a catalytic asymmetric method for the synthesis of enantioenriched cyclohexanes from 1,5-diols via hydrogen borrowing catalysis. This reaction is mediated by the addition of a chiral iridium(I) complex, which is able to impart high levels of enantioselectivity upon the process. A series of enantioenriched cyclohexanes have been prepared and the mode of enantioinduction has been probed by a combination of experimental and DFT studies.
3-chloropropyl and 4-chlorobutyl phenyl ethers as sources of 1,3-dilithiopropane and 1,4-dilithiobutane: Sequential reaction with carbonyl compounds
Foubelo, Francisco,Saleh, Sadiq A.,Yus, Miguel
, p. 3478 - 3483 (2007/10/03)
The reaction of 3-chloropropyl and 4-chlorobutyl phenyl ethers (1) with lithium powder and a catalytic amount of DTBB (5% molar) in THF at - 78 °C followed by successive treatment with a carbonyl compound [R1R2CO = ButCHO, Me2CO, (CH2)5CO, (-)-menthone] at -78 to 20 °C and, after 1.5 h at this temperature, with a second one [R3R4CO = Bu1CHO, PhCHO, Me2CO, MeCOPrn, (CH2)5CO, (-)-menthone] at -78 °C leads, after hydrolysis with water, to the corresponding 1,5-and 1,6-diols (2). Because of the competition of two different reductive cleavages, 1,4- and 1,5-diols 3 were also obtained as side-reaction products.
