126524-00-3Relevant academic research and scientific papers
Direct enantioselective C(sp3)-H acylation for the synthesis of α-amino ketones
Shu, Xiaomin,Huan, Leitao,Huang, Qian,Huo, Haohua
supporting information, p. 19058 - 19064 (2020/11/13)
A direct enantioselective acylation of α-amino C(sp3)-H bonds with carboxylic acids has been achieved via the merger of transition metal and photoredox catalysis. This straightforward protocol enables cross-coupling of a wide range of carboxylic acids, one class of feedstock chemicals, with readily available N-alkyl benzamides to produce highly valuable α-amino ketones in high enantioselectivities under mild conditions. The synthetic utility of this method is further demonstrated by gram scale synthesis and application to late-stage functionalization. This method provides an unprecedented solution to address the challenging stereocontrol in metallaphotoredox catalysis and C(sp3)-H functionalization. Mechanistic studies suggest the α-C(sp3)-H bond of the benzamide coupling partner is cleavage by photocatalytically generated bromine radicals to form α-amino alkyl radicals, which subsequently engages in nickel-catalyzed asymmetric acylation.
The synthesis and biological characterization of a ceramide library
Chang, Young-Tae,Choi, Jaehwa,Ding, Sheng,Prieschl, Eva E.,Baumruker, Thomas,Lee, Jae-Mok,Chung, Sung-Kee,Schultz, Peter G.
, p. 1856 - 1857 (2007/10/03)
A facile synthesis of a combinatorial ceramide library and their activities in the NF-κB pathway and in apoptosis induction/prevention were demonstrated. A novel NF-κB activating molecule was discovered among ceramide containing β-galactose, and the structural requirements of ceramides for apoptosis induction was elucidated. Copyright
THERMAL CYCLIZATION OF Β-HYDROXYAMIDES TO OXAZOLINES
Somanathan, Ratnasamy,Aguilar, Hugo R.,Rivero, Ignacio A.,Aguirre, Gerardo,Hellberg, Lars H.,Yu, Zheng,Thomas, Jacquelin A.
, p. 348 - 353 (2007/10/03)
Thermal conversion of amides derived from erythro and threo ephedrines yields stereospecific oxazolines.
Stereoselective synthesis of 1,2-amino alcohols by asymmetric borane reduction of α-oxoketoxime ethers
Masui, Moriyasu,Shioiri, Takayuki
, p. 5195 - 5198 (2007/10/03)
Asymmetric reduction of α-oxoketoxime ethers with the reagents prepared in situ from trimethyl borate and chiral amino alcohols derived from either L-proline or α-pinene was investigated. Both cyclic and acyclic α- oxoketoxime ethers were reduced to afford the corresponding chiral 1,2amino alcohols with high enantioselectivities.
(DIETHYLAMINO)SULFUR TRIFLUORIDE (DAST) AS A USEFUL REAGENT FOR THE PREPARATION OF 2-OXAZOLINES FROM 1,2-AMIDO ALCOHOLS
Lafargue, Pierre,Guenot, Pierre,Lellouche, Jean-Paul
, p. 947 - 958 (2007/10/02)
Acylic 1,2-amido alcohols (6) react efficiently with a slight excess of (diethylamino)sulfur trifluoride (DAST) to afford the corresponding 2-oxazolines (10) in good yields ranging between 57-95percent.Even at the low temperature of -78 deg C, a rapid ( 1 h) and stereoselective amide cyclization is observed without formation of acylaziridine by-products.The scope of this cyclization is discussed.
Ruthenium-catalyzed oxidations for selective syntheses of ketones and acyl cyanides. Selective acylation of amino compounds with acyl cyanides
Murahashi,Naota
, p. 433 - 440 (2007/10/02)
Oxidation of alcohols to the corresponding carbonyl compounds with tert-butyl hydroperoxide in the presence of dichlorotris(triphenylphosphine)ruthenium catalyst gives the corresponding carbonyl compounds with high efficiency. This method can be applied to the oxidation of cyanohydrins to give acyl cyanides which are versatile synthetic intermediates. Acylation of amino compounds with acyl cyanides thus obtained proceeds chemoselectively. Thus, the reaction of amino alcohols with acyl cynides gives N-acylated products exclusively. In the similar N-acylation of polyamines primary amines are selectively acylated in the presence of secondary amines. These reactions are highly useful for the synthesis of spermidine and spermine alkaloids such as spermidine alkaloids such as spermidine siderophores. Dimeric cyclocoupling reaction of diacyl cyanides such as iso- and terephthaloyl cyanides with polyamines can be performed under the similar reaction conditions to give the corresponding polyazamacrocycles with high efficiency.
N-ALKYLOXAZABOROLIDINES DERIVED FROM EPHEDRINES
Tlahuext, Hugo,Contreras, Rosalinda
, p. 727 - 730 (2007/10/02)
The synthesis of oxazaborolidines from amides derived from ephedrine and pseudoephedrine by treatment with BH3-THF is reported.The reaction affords chiral oxazaborolidines with nitrogen atom substituents of different steric requirements enlarging the pote
NON-CATALYTIC REDUCTION OF Α-OXIMINOKETONES AND Α-OXIMINOALCOHOLS TO ERYTHRO-2-AMINO-1-ARYLALKAN-1-OLS
Oppong-Boachie, Francis Kwabena
, p. 293 - 298 (2007/10/02)
A non-catalytic reduction of α-oximinoketones 1 and α-oximinoalcohols 2 to erythro-2-amino-1-arylalkan-1-ols 3 with lithium aluminium hydride is reported.The erythro-2-amino-1-arylalkan-1-ols are isolated as their hydrochlorides 5 and characterised as the erythro isomers by benzoylation.
STEREOCHEMICAL COURSE OF THE REACTION OF 2-HALOETHYL ISOTHIOCYANATES WITH NUCLEOPHILES. sTEREOSPECIFIC ROUTE TO 4,5-DISUBSTITUTED Δ2-THIAZOLINES AND THIAZOLIDINE-2-THIONES
Kniezo, Ladislav,Kristian, Pavol,Budesinsky, Milos,Havrilova, Katarina
, p. 717 - 728 (2007/10/02)
Diastereoisomeric 1-chloro-1-phenyl-2-isothiocyanatopropanes have been prepared.They reacted stereospecifically with CH3ONa, diethylamine, aniline and NaSH to give pure cis or trans-4,5-disubstituted Δ2-thiazolines and thiazolidine-2-thiones whose configuration was determined using the nuclear Overhauser effect.The preponderant conformation of diastereoisomeric 1-chloro-1-phenyl-2-isothiocyanatopropanes was estimated on the basis of coupling constants of vicinal protons.
