168907-66-2Relevant articles and documents
Catalytic asymmetric intramolecular homologation of ketones with α-diazoesters: Synthesis of cyclic α-Aryl/Alkyl β-ketoesters
Li, Wei,Tan, Fei,Hao, Xiaoyu,Wang, Gang,Tang, Yu,Liu, Xiaohua,Lin, Lili,Feng, Xiaoming
supporting information, p. 1608 - 1611 (2015/01/30)
A catalytic asymmetric intramolecular homologation of simple ketones with α-diazoesters was firstly accomplished with a chiral N,N′-dioxide-Sc(OTf)3 complex. This method provides an efficient access to chiral cyclic α-aryl/alkyl β-ketoesters containing an all-carbon quaternary stereocenter. Under mild conditions, a variety of aryl- and alkyl-substituted ketone groups reacted with α-diazoester groups smoothly through an intramolecular addition/rearrangement process, producing the β-ketoesters in high yield and enantiomeric excess.
Process for production of piperidine derivatives
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Page/Page column 14, (2008/06/13)
Processes are disclosed for preparing piperidine derivative compounds of the formulae I, II or III: The processes involve reacting a compound of formula Ia, IIa or IIIa with isobutyrate or an isobutyrate equivalent.
Process for production of carebastine
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Page/Page column 20, (2008/06/13)
Processes are disclosed for preparing piperidine derivative compounds of the formulae I, II or III:
Synthesis of Aryl 3-(2-Imidazolyl)propyl Ketones.
Davis, Frank S.,Huang, Liang-fu,Bauer, Ludwig
, p. 915 - 920 (2007/10/02)
The approach to the title compounds was via lithiation-substitution of N-methyl or N-(triphenylmethyl)imidazole by some iodo ketals. 4-Chloro-4'-halobutyrophenones (halo = F, Cl, Br) were converted by sodium iodide to the corresponding aliphatic iodides which were subsequently ketalized with ethylene glycol to provide the corresponding iodo ketals.Lithiation of either 1-methyl- or 1-(triphenylmethyl)imidazole with n-butyllithium generated the corresponding 2-lithioimidazoles, in situ, which were then reacted with these iodo ketals to form the corresponding C-2 substitute d imidazoles.Dilute aqueous acid hydrolysis released the ketone from the ketal.For N-triphenylmethyl protected imidazoles, the triphenylmethyl group was also hydrolyzed to give triphenylmethanol and 3-(2-imidazolyl)propyl 4-haloaryl ketones.These N-unsubstituted imidazolyl ketones can be alkylated independently with triphenylmethyl chloride to form the corresponding N-triphenylmethyl imidazole derivatives.