17831-02-6Relevant articles and documents
A synthetic amino acid N-methylation method and its product and application (by machine translation)
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Paragraph 0053; 0054; 0055, (2016/11/09)
The invention belongs to the technical field of amino acid polypeptide synthesis, discloses a synthetic amino acid N-methylation method and its product and application. This method passes the benzyl protection of a carboxyl group of the amino acid, trifluoroacetyl protection of the amino group, after methylation, get N-methylation of the amino acid. N obtained by the method of this invention-methyl (trifluoro-acetyl)-amino acid benzyl ester, can be directly used for polypeptide synthesis N-methyl structure having the amino acid benzyl ester product, and it has good selective deprotection of, its N the C-end-to-end and selectively deprotected. With foreign Ag 2 O/CH 3 I/Boc method (hypertoxic, high cost) and NaH / (CH 3 O) 2 SO 2 method compared with (hypertoxic), and the like, the method of the invention high yield, the use of the virulent reagent-free, safe and non-toxic, the operation is simple, common reagent to the raw material, the cost is low, and the structure strong pertinence, racemation a low possibility of the product obtained, it has broad industrial prospects. (by machine translation)
Enantioselective synthesis of 1,2,4-triazolines by chiral iron(ii)-complex catalyzed cyclization of α-isocyano esters and azodicarboxylates
Wang, Min,Liu, Xiaohua,He, Peng,Lin, Lili,Feng, Xiaoming
supporting information, p. 2572 - 2574 (2013/04/10)
Enantioselective cyclization of α-isocyano esters with azodicarboxylates catalyzed by FeII-N,N′-dioxide complexes has been developed. Under mild conditions, a variety of 1,2,4-triazoline derivatives was obtained in high yields and enantioselectivities.
Well-defined binuclear chiral spiro copper catalysts for enantioselective N-H insertion
Zhu, Shou-Fei,Xu, Bin,Wang, Guo-Peng,Zhou, Qi-Lin
, p. 436 - 442 (2012/03/07)
An asymmetric N-H insertion of α-diazoesters with anilines catalyzed by well-defined copper complexes of chiral spiro bisoxazoline ligands was studied in detail. The copper-catalyzed asymmetric N-H insertion of a wide range of α-alkyl-α-diazoacetates with anilines was accomplished with excellent enantioselectivity (up to 98% ee) and provided an efficient method for the preparation of optically active α-amino acid derivatives. A correlation study of the electronic properties of the substrates with the enantioselectivity of the N-H insertion reaction supports a stepwise insertion mechanism, and the significant first-order kinetic isotope effect proves that the proton transfer is most likely the rate-limiting step. A binuclear chiral spiro copper catalyst having 14-electron copper centers, a trans coordination model, a perfect C2-symmetric chiral pocket, and significant Cu-Cu interaction was isolated and extensively studied. The novel structure of the binuclear chiral spiro copper catalyst leads to unique reactivity as well as enantioselectivity in the N-H insertion reaction.
