64222-28-2Relevant academic research and scientific papers
Enantioselective intermolecular carbon-carbon bond formation of glyoxylate imines with allylstannanes catalyzed by tropos BIPHEP-gold(I) complexes with Au-Au interactions
Kojima, Masafumi,Mikami, Koichi
, p. 13950 - 13953 (2011)
Interactions act: The enantioselective allylation reaction of glyoxylate imines catalyzed by tropos DM-BIPHEP-gold(I) complexes with an Au-Au interaction was developed to give a higher enantioselectivity than the atropos DM-BINAP-gold complexes without an
Transformation of Racemic Azlactones into Enantioenriched Dihydropyrroles and Lactones Enabled by Hydrogen-Bond Organocatalysis
?abka, Matej,Kocian, Adrián,Bilka, Stanislav,Andrej?ák, Samuel,?ebesta, Radovan
, p. 6077 - 6087 (2019/09/12)
Azlactones, a potent building block for the synthesis of complex molecules, have been explored in an organocatalytic Mannich reaction with protected imines. In this study, azlactones containing a propargyl substituent were employed for the first time in organocatalysis so far. The catalytically active species responsible for high enantioselectivity with substrate containing such a small linear substituent is assembled in situ from a bifunctional thiourea, prone to dimerization, and an organic acid, as evidenced by DOSY NMR. The resulting α,β-diamino acid derivatives were subjected to further derivatization: as an example, gold-catalyzed intramolecular hydroamination of alkynes gave chiral spirocyclic dihydropyrrole. Alternatively, related squaramide catalyst enabled a Mannich reaction of azlactones with N-aryl or alkyl glyoxylate imines. Reduction of these adducts gave access to 2,3-diaminobutyrolactones or 2,3-diamino-1,4-diol with a tertiary and a quaternary stereocenter.
Visible-Light-Mediated, Chemo- and Stereoselective Radical Process for the Synthesis of C-Glycoamino Acids
Ji, Peng,Zhang, Yueteng,Wei, Yongyi,Huang, He,Hu, Wenbo,Mariano, Patrick A.,Wang, Wei
supporting information, p. 3086 - 3092 (2019/05/01)
An approach for efficient synthesis of C-glycosyl amino acids is described. Different from typical photoredox-catalyzed reactions of imines, the new process follows a pathway in which α-imino esters serve as electrophiles in chemoselective addition reactions with nucleophilic glycosyl radicals. The process is highlighted by the mild nature of the reaction conditions, the highly stereoselectivity attending C-C bond formation, and its applicability to C-glycosylations using both armed and disarmed pentose and hexose derivatives.
A new entry to azomethine ylides from allylic amines and glyoxals: Shifting the reliance on amino ester precursors
Machamer, Natalie K.,Liu, Xiaoxi,Waters, Stephen P.
supporting information, p. 4996 - 4999 (2014/12/11)
The first examples of azomethine ylides derived from allylic amine and glyoxal precursors are reported. The condensation of primary allylic and α-aryl amines with glyoxylates or α-aryl glyoxals affords conjugated azomethine ylides that undergo facile [3 +
Synthesis of new 1, 4-Dihydropyridines by addition-rearrangement process with imine derivatives and β-Ketoester as starting materials in solvent-free conditions
Xueming, Chen,Xiaoguang, Huang,Yunyun, Chen,Feng, He,Xingshu, Li
experimental part, p. 213 - 218 (2010/04/23)
N-substituted 1, 4-dihydropyridines bearing a carboxyl group at the 4-position were synthesized in solvent-free conditions with Cu2+ as the catalyst, imine and β-ketoester as starting materials. The possible mechanism which consists of addition
Method for the synthesis of 4-hydroxyisoleucine and the derivatives thereof
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Page/Page column 5-6, (2008/06/13)
The invention relates to a method for the synthesis of two isomers, at function OH, alone or in mixtures, of amino acids α or the derivatives thereof, having general formula (B), wherein: linkage C—O of the 4-position carbon (represented by symbol) denotes one or other of isomers III or IV, or mixtures thereof. Moreover, R1 and R2 represent: a hydrogen atom; or either R1 or R2 represents a hydrogen atom and the other substituent is a radical Ra, an acyl group —CORa, such as acetyl, or a functional group —COORa, —SO2Ra, —N (Ra, Rb), Ra and Rb, which are identical or different, representing a C1-C12 linear or branched alkyl radical, optionally substituted, an aryl group with one or more aromatic rings and heterocycles, comprising between 5 and 8C, optionally substituted, or aralkyl, the alkyl substituent and the aryl group being as defined above; or R1 and R2 both represent a substituent as defined above. R3 represents a hydrogen atom or Ra and R4 has the significance of Ra. The invention is characterised in that it comprises: the isomerisation of a compound having formula (I), wherein R1, R2, Ra, R3 and R4 are as defined above, such as to produce a compound having formula (II); and the reduction of the carbonyl function thereof which, depending on the catalytic system employed and the formula (I) compound used, produces one of the isomers having general formula (III) or (IV) or a mixture thereof having formula (B). The invention can be used for the synthesis of (2S, 3R, 4S)-4-hydroxyisoleucine.
Diastereochemical diversity of imidazoline scaffolds via substrate controlled TMSCI mediated cycloaddition of azlactones
Sharma, Vasudha,Tepe, Jetze J.
, p. 5091 - 5094 (2007/10/03)
(Chemical Equation Presented) We report herein a trimethylsilyl chloride mediated substrate controlled 1,3-dipolar cycloaddition for the diastereoselective synthesis of either syn- or anti-imidazolines. This method provides scaffolds with four points of diversity and control over two stereocenters.
Synthesis of α-(3-indolyl)glycine derivatives via spontaneous Friedel-Crafts reaction between indoles and glyoxylate imines
Jiang, Biao,Huang, Zuo-Gang
, p. 2198 - 2204 (2007/10/03)
Mannich-type Friedel-Crafts reaction between indoles and ethyl glyoxylate imines proceeded spontaneously in the absence of an acid catalyst. Ethyl α-(3-indolyl)glycinates were obtained in moderate to high yields. Reaction with (R)-α-methylbenzylamine deri
Ytterbium triflate catalyzed electrophilic substitution of indoles: The synthesis of unnatural tryptophan derivatives
Janczuk, Adam,Zhang, Wei,Xie, Wenhua,Lou, Sanzhong,Cheng, JinPei,Wang, Peng G.
, p. 4271 - 4274 (2007/10/03)
Benzylamine was combined with ethyl glyoxylate to form the intermediate imine which in the presence of catalytic amount of Yb(OTf)3 underwent electrophilic substitution on the 3-position of a variety of indoles to produce unnatural tryptophan d
