23025-55-0Relevant articles and documents
Stereo-controlled asymmetric bioreduction of α,β-dehydroamino acid derivatives
Stueckler, Clemens,Winkler, Christoph K.,Hall, Melanie,Hauer, Bernhard,Bonnekessel, Melanie,Zangger, Klaus,Faber, Kurt
supporting information; experimental part, p. 1169 - 1173 (2011/07/09)
α,β-Dehydroamino acid derivatives proved to be a novel substrate class for ene-reductases from the 'old yellow enzyme' (OYE) family. Whereas N-acylamino substituents were tolerated in the α-position, β-analogues were generally unreactive. For aspartic aci
Reaction of N-(p-Tolylsulfonyl)diphenylcyclopropenimine with Pyridinium and Isoquinolinium Ylides
Pilli, Ronaldo Aloise,Rodrigues, J. Augusto,Kascheres, Albert
, p. 1084 - 1091 (2007/10/02)
N-(p-Tolylsulfonyl)diphenylcyclopropenimine (2) reacted smoothly with pyridinium N-carbethoxyamide (3) to afford a new ylide (5), in addition to stilbene 4, uracil 6, and pyrimidone 7.An observed thermal transformation of 5 to 6 and 7 is discussed.Reaction of the cyanocarboethoxy methylides 15a-c with 2 produced the internal salts 16a-c, while the dicarbethoxy, monocarbethoxy, and benzoyl methylides 15d-f gave the pyridine-free cyclics 26, 28, and 29, respectively.The isoquinolinium methylides 31a-c reacted in an analogous fashion, while the N-amides 33a,b afforded cycloadducts 34a,b.A series of reactions used to correlate the structures of the latter is described, including an observed cycloaddition mode for diphenylcyclopropenone (1) with 33a-c which yielded 39, 37, and 42, respectively.
Investigation of Thermally Induced α-Deoxysilylation of Organosilylated Hydroxylamine Derivatives as a General Method for Nitrene Production
Chang, Young Hwan,Chiu, Fang-Ting,Zon, Gerald
, p. 342 - 354 (2007/10/02)
A variety of organosilylated hydroxylamine derivatives have been synthesized and studied as possible nitrene generators by thermally induced α-deoxysilylation: GN(OR')SiR3 GN + R'OSiR3, where G = EtO2C, ArCO, ArSO2, Me, H, and Ph2PO.The methods used to assess nitrene formation include trapping product characterization, substitutent variation, kinetic activation parameter measurements, Hammett studies, and solvent effects.While the latter two types of precursors were only briefly investigated because of their marked resistance to fragmentation, the combined data for the remaining compounds are consistent with the intermediacy of a nitrene.The existence of alternative deoxysilylation pathways is discussed in some cases, and for comparison with the nitrogen systems reported herein, kinetic activation parameters for α-deoxysilylation about carbon and silicon have been determined.