124443-68-1Relevant articles and documents
Sustainable Route Toward N-Boc Amines: AuCl3/CuI-Catalyzed N-tert-butyloxycarbonylation of Amines at Room Temperature
Cao, Yanwei,He, Lin,Huang, Yang
, (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.
Iodoarene-Catalyzed Oxyamination of Unactivated Alkenes to Synthesize 5-Imino-2-Tetrahydrofuranyl Methanamine Derivatives
Deng, Xiao-Jun,Liu, Hui-Xia,Zhang, Lu-Wen,Zhang, Guan-Yu,Yu, Zhi-Xiang,He, Wei
, p. 235 - 253 (2021/01/09)
Reported here is the room-temperature metal-free iodoarene-catalyzed oxyamination of unactivated alkenes. In this process, the alkenes are difunctionalized by the oxygen atom of the amide group and the nitrogen in an exogenous HNTs2 molecule. This mild and open-air reaction provided an efficient synthesis to N-bistosyl-substituted 5-imino-2-tetrahydrofuranyl methanamine derivatives, which are important motifs in drug development and biological studies. Mechanistic study based on experiments and density functional theory calculations showed that this transformation proceeds via activation of the substrate alkene by an in situ generated cationic iodonium(III) intermediate, which is subsequently attacked by an oxygen atom (instead of nitrogen) of amides to form a five-membered ring intermediate. Finally, this intermediate undergoes an SN2 reaction by NTs2 as the nucleophile to give the oxygen and nitrogen difunctionalized 5-imino-2-tetrahydrofuranyl methanamine product. An asymmetric variant of the present alkene oxyamination using chiral iodoarenes as catalysts also gave promising results for some of the substrates.
Preparation method of 2-(4-piperidyl)-2-propanol and hydrochloride thereof
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Paragraph 0032-0034, (2020/09/12)
The invention provides a preparation method of 2-(4-piperidyl)-2-propanol and hydrochloride thereof. The method comprises the following steps: introducing tert-butyloxycarboryl as an amino protectiongroup on a raw material 4-piperidinecarboxylate molecule, carrying out alkylation addition on an ester group in the raw material molecule by using a methyl Grignard reagent, removing a BOC protectiongroup in an acidolysis manner to obtain 2-(4-piperidinyl)-2-propanol hydrochloride, and adding an alkali to adjust the pH value in order to obtain 2-(4-piperidinyl)-2-2-propanol. The preparation method provided by the invention is simple, easy to operate and high in yield, has the cost advantage and is very suitable for industrial production.