Urea derivatives based on a 1,1′-binaphthalene skeleton as chiral solvating agents for sulfoxides

Method for determination of optical purity of 2‐arylpropanoic acids using urea derivatives based on a 1,1′‐binaphthalene skeleton as chiral NMR solvating agents: Advantages and limitations thereof

“…31 In addition, compound 1 is often used by chemists as an enantioselective catalyst [33][34][35][36] in various reactions. All the ureas can be easily prepared from the commercially available starting materials in a one-step synthesis.…”

“…31 The resulting diastereomeric complexes are based on hydrogen bonding, which, in principle, also makes these compounds suitable candidates for complexation of profens. 31 The resulting diastereomeric complexes are based on hydrogen bonding, which, in principle, also makes these compounds suitable candidates for complexation of profens.…”

“…31 Racemic ibuprofen 6, naproxen 7, etodolac 12, loxoprofen 13, and zaltoprofen 14 were purchased from Fluorochem, Hadfield, United Kingdom. 31 Racemic ibuprofen 6, naproxen 7, etodolac 12, loxoprofen 13, and zaltoprofen 14 were purchased from Fluorochem, Hadfield, United Kingdom.…”

“…Compounds 1 to 5 were synthesized in our laboratory previously. 31 Racemic ibuprofen 6, naproxen 7, etodolac 12, loxoprofen 13, and zaltoprofen 14 were purchased from Fluorochem, Hadfield, United Kingdom. Ketoprofen 9 was purchased from Sigma-Aldrich.…”

Enantioselective complexation of 1‐phenylethanol with chiral compounds bearing urea moiety

“…(R a )-2,2′-bis(N′-hexyl)ureido-1,1′-binaphthalene (2) was prepared according to literature. 16 (S a )-2,2′-bis(acetylamino)-1,1′-binaphthalene (3). (S a )-2,2′-amino-1,1′-binaphthalene (5 g, 17.6 mmol) was stirred with acetic acid (99%, 16.07 g, 15.3 mL, 0.27 mol) in dichloromethane (200 mL).…”