Adamek, Jakub; Zielezny, Paulina; Erfurt, Karol published an article in 2021. The article was titled 《Synthesis of N-Protected 1-Aminoalkylphosphonium Salts from Amides, Carbamates, Lactams, or Imides》, and you may find the article in Journal of Organic Chemistry.Electric Literature of C5H11NO2 The information in the text is summarized as follows:
This report describes the development and optimization of the one-pot method for the synthesis of N-protected 1-aminoalkylphosphonium salts [R1CONR2CHR3P+Ar3]X based on the three-component coupling of aldehydes R3CHO and either amides, carbamates, lactams, imides, or ureas R1CONHR2 in the presence of triarylphosphonium salts [Ar3PH]X. The proposed strategy is very efficient and easy to carry out even on a larger scale (20 g) in any typical laboratory Most reactions occur at temperatures between 50 and 100° in a short time (1-2 h) without requiring any catalyst, and simple workup procedures afford good to excellent yields. The exceptions are condensations with imides, which require much higher temperatures (150-170°) and longer reaction times (even 30 h). The possibility of carrying out the synthesis under solvent-free conditions (neat reactions) is also demonstrated. Finally, we prove the developed one-pot methodol. can be successfully applied for the synthesis of structurally diverse N-protected 1-aminoalkylphosphonium salts. Mechanistic studies showed the intermediate products of described couplings are 1-hydroxyalkylphosphonium salts, not N-hydroxyalkylamides, -imides, etc., as initially expected. In the part of experimental materials, we found many familiar compounds, such as tert-Butyl carbamate(cas: 4248-19-5Electric Literature of C5H11NO2)
tert-Butyl carbamate(cas: 4248-19-5) belongs to anime. Primary amines having a tertiary alkyl group (R3CNH2) are difficult to prepare with most methods but are made industrially by the Ritter reaction. In this method a tertiary alcohol reacts with hydrogen cyanide (HCN) in the presence of a concentrated strong acid; a formamide, RNH―CHO, is formed first, which then undergoes hydrolysis.Electric Literature of C5H11NO2
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