85275-45-2Relevant articles and documents
Sustainable Route Toward N-Boc Amines: AuCl3/CuI-Catalyzed N-tert-butyloxycarbonylation of Amines at Room Temperature
Cao, Yanwei,Huang, Yang,He, Lin
, (2021/12/22)
N-tert-butoxycarbonyl (N-Boc) amines are useful intermediates in synthetic/medicinal chemistry. Traditionally, they are prepared via an indirect phosgene route with poor atom economy. Herein, a step- and atom-economic synthesis of N-Boc amines from amines, t-butanol, and CO was reported at room temperature. Notably, this N-tert-butyloxycarbonylation procedure utilized ready-made substrates, commercially available AuCl3/CuI as catalysts, and O2 from air as the sole oxidant. This catalytic system provided unique selectivity for N-Boc amines in good yields. More significantly, gram-scale preparation of medicinally important N-Boc amine intermediates was successfully implement, which demonstrated a potential application prospect in industrial syntheses. Furthermore, this approach also showed good compatibility with tertiary and other useful alcohols. Investigations of the mechanisms revealed that gold catalyzed the reaction and copper acted as electron transfer mediator in the catalytic cycle.
Preparation method of (S)-N-BOC-3-hydroxypiperidine
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Paragraph 0060; 0067-0069; 0074; 0075; 0080, (2020/02/17)
The invention provides a preparation method of (S)-N-BOC-3-hydroxypiperidine. The preparation method comprises the following steps: carrying out a reaction on (S)-epichlorohydrin with a 2-chloroethylmagnesium bromide Grignard reagent to obtain (S)-1,5-dichloro-2-pentanol, carrying out an intramolecular cyclization reaction in the presence of an alkaline substance to generate (S)-5-chloro-1,2-epoxypentane, carrying out a reaction on the (S)-5-chloro-1,2-epoxypentane with an ammonia solution to generate (S)-1-amino-5-chloro-2-pentanol, then carrying out an intramolecular cyclization reaction onthe (S)-1-amino-5-chloro-2-pentanol to obtain (S)-3-hydroxypiperidine, and finally carrying out a reaction with BOC anhydride to obtain the product (S)-N-BOC-3-hydroxypiperidine. The preparation method disclosed by the invention has the advantages of short synthesis route, few side reactions and high yield; the product has good quality and is convenient for purification. The raw materials are easily available and has low price; the reaction conditions are mild; and safety is high. The preparation method is environmentally friendly, is simple and practice, and is suitable for industrial batchproduction.
PYRAZOLE DERIVATIVES AS H4 ANTAGONIST COMPOUNDS
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Paragraph 37; 46; 47, (2020/05/21)
The disclosures herein relate to novel compounds of formula (1): and salts thereof, wherein A; X;n; R1 and R2 are defined herein, and their use in treating, preventing, ameliorating, controlling or reducing the risk of disorders associated with H4 receptors.