- Decarboxylative hydrazination of unactivated carboxylic acids by cerium photocatalysis
-
We report the cerium photocatalyzed radical decarboxylative hydrazination of carboxylic acids with di-tert-butylazodicarboxylate (DBAD). The operationally simple protocol provides rapid access to synthetically useful hydrazine derivatives and overcomes current scope limitations in the photoredox-catalyzed decarboxylation of carboxylic acids.
- Yatham, Veera Reddy,Bellotti, Peter,K?nig, Burkhard
-
supporting information
p. 3489 - 3492
(2019/03/26)
-
- Synthesis method for pharmaceutically acceptable salt of alkylhydrazine
-
The invention discloses a synthesis method for pharmaceutically acceptable salt of alkylhydrazine. According to the method, with hydrazine hydrate and BOC anhydride as starting raw materials, BOC hydrazine is synthesized firstly, then alkyl compounds are added in, BOC alkylhydrazine is obtained, finally BOC is removed, and the pharmaceutically acceptable salt of the corresponding alkylhydrazine is obtained in a conversion manner. According to the synthesis method, the raw materials for use are low in price and cost and easy to obtain. The synthesis method is short in synthesis route and high in yield, the obtained product is high in chemical purity, special production equipment is not needed for all reactions, and obtained intermediates and the final product do not need column chromatography and crystallization and purification.
- -
-
Paragraph 0038; 0048; 0057; 0058
(2017/08/28)
-
- Three-membered Heterocycles,10. - Phosphonohydrazidic Esters by Alkoxide-induced Rearrangement of N-Chlorophosphonic Diamides
-
Phosphoric and phosphonic amides 8 are formed from phosphoric and phosphonic chlorides 6 and primary amines 7 in high yields. 2,5-Dimethyl-2,5-hexanediamine (7e) reacts with phenylphosphonic dichloride (6c) to give the perhydro-1,3,2-diazaphosphepine 8h.The amides 8 are converted almost quantitatively into the N-chlorophosphoric and N-chlorophosphonic amides 9 by means of tert-butyl hypochlorite.The N,N'-di-tert-alkyl-N-chlorophosphonic diamides 9 derived from methyl-, tert-butyl-, or phenylphosphonic acid react with methoxide or tertiary alkoxides to afford the phosphonohydrazidic esters 10-13.The methyl ester 10d is also formed from 1,2,3-tri-tert-butyldiazaphosphiridine 3-oxide (14) and methanol. 1H-, 13C-, and 31P-NMR spectra prove that the sharply melting phosphonohydrazidic esters 10-13 exist in solution as two diastereomers with ratios ranging from 9:1 to 6:4.The hydrazidic methyl ester 10d which was investigated as a representative example exhibits a temperature dependent 1H-NMR spectrum.Due to the presence of the tert-alkyl groups, inversion at the tertiary nitrogen atom is slow on each NMR time scale. The independence of the IR spectrum on the concentration shows that the predominant diastereomer of 10d is stabilized by an intramolecular hydrogen bond.The electron impact induced decomposition of the amides 8, N-chloroamides 9, and phosphonohydrazidic esters 10-13 ultimately produces cations which are derived from monomeric metaphosphoric or metaphosphonic acid. 6 N hydrochloric acid first splits off the P-N-tert-butyl group of the methyl ester 10d to give the intermediate 15 which can be isolated or which undergoes further hydrolysis to tert-butylphosphonic acid (17) and tert-butylhydrazine(19).The tert-butyl ester 11d yields the same final products in hot hydrochloric acid.At low temperatures and short reaction times, however, di-tert-butylhydrazine (18) is formed.
- Quast, Helmut,Heuschmann, Manfred,Abdel-Rahman, Mohamed O.
-
p. 943 - 966
(2007/10/02)
-
