17118-74-0Relevant articles and documents
A single-step synthesis of xyridins A and B, metabolites from Xyris indica
Saeed, Aamer
, p. 967 - 972 (2005)
A facile single-step synthesis of the title isocoumarins isolated from Xyris indica has been elaborated. Condensation of butanoyl chloride and 2-oxobutanoyl chloride with 3,4-methylenedioxyhomophthalic acid afforded xyridin A and xyridin B, respectively. Xyridin A was saponified to the corresponding keto acid, which on reduction gave the (±)-3,4-dihydro-6,7- methylenedioxy-3-propylisocoumarin in which diastereotopy of the methylenic protons around the stereogenic center was observed. A mass fragmentation mechanism for xyridins has also been suggested.
Exploiting the Reactivity of 1,2-Ketoamides: Enantioselective Synthesis of Functionalized Pyrrolidines and Pyrrolo-1,4-benzodiazepine-2,5-diones
Acosta, Paola,Becerra, Diana,Goudedranche, Sébastien,Quiroga, Jairo,Constantieux, Thierry,Bonne, Damien,Rodriguez, Jean
, p. 1591 - 1595 (2015)
A new strategy for the synthesis of optically active pyrrolo[1,4]benzodiazepine-2,5-diones has been developed. The approach is based on an initial Michael addition of functionalized 1,2-ketoamides on nitroalkenes, with a reduction-double cyclization seque
Hydroxoiridium/Chiral Diene Complexes as Effective Catalysts for Asymmetric Annulation of α-Oxo- and Iminocarboxamides with 1,3-Dienes
Hatano, Miyuki,Nishimura, Takahiro
supporting information, p. 10949 - 10952 (2015/09/15)
The asymmetric [3+2] annulation of α-oxo- and α-iminocarboxamides with 1,3-dienes catalyzed by hydroxoiridium/chiral diene complexes was realized, giving high yields of the corresponding γ-lactams with high enantioselectivity. [3+2] annulation: The asymme
Cationic Ir/Me-BIPAM-catalyzed asymmetric intramolecular direct hydroarylation of α-ketoamides
Shirai, Tomohiko,Ito, Hajime,Yamamoto, Yasunori
supporting information, p. 2658 - 2661 (2014/03/21)
Asymmetric intramolecular direct hydroarylation of α-ketoamides gives various types of optically active 3-substituted 3-hydroxy-2-oxindoles in high yields with complete regioselectivity and high enantioselectivities (84-98 % ee). This is realized by the use of the cationic iridium complex [Ir(cod) 2](BArF4) and the chiral O-linked bidentate phosphoramidite (R,R)-Me-BIPAM. Carbon's got a brand new bond: Asymmetric intramolecular direct hydroarylation of α-ketoamides gives various optically active 3-substituted 3-hydroxy-2-oxindoles in high yields with complete regioselectivity and high enantioselectivities. This is realized by the use of an asymmetric cationic iridium complex formed in situ (see Scheme).
A new class of tunable dendritic diphosphine ligands: Synthesis and applications in the Ru-catalyzed asymmetric hydrogenation of functionalized ketones
Ma, Baode,Miao, Tingting,Sun, Yihua,He, Yanmei,Liu, Ji,Feng, Yu,Chen, Hui,Fan, Qing-Hua
supporting information, p. 9969 - 9978 (2014/08/18)
A series of tunable G0-G3 dendritic 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (BINAP) ligands was prepared by attaching polyaryl ether dendrons onto the four phenyl rings on the P atoms. Their ruthenium complexes were employed in the asymmetric hydrogenation of β-ketoesters, α-ketoesters, and α-ketoamides to reveal the effects of dendron size on the catalytic properties. The second- and third-generation catalysts exhibited excellent enantioselectivities, which are remarkably higher than those obtained from the small molecular catalysts and the first-generation catalyst. Molecular modeling indicates that the incorporation of bulky dendritic wedges can influence the steric environments around the metal center. In addition, the ruthenium catalyst bearing a second-generation dendritic ligand could be recycled and reused seven times without any obvious decrease in enantioselectivity.
A temporary-bridge strategy for enantioselective organocatalyzed synthesis of aza-seven-membered rings
Goudedranche, Sbastien,Pierrot, David,Constantieux, Thierry,Bonne, Damien,Rodriguez, Jean
supporting information, p. 15605 - 15608 (2015/01/08)
We report the first enantioselective organocatalyzed domino synthesis of azepane moieties. This temporary-bridge strategy is based on a conceptually original annulation of ambident electrophilic and 1,4-bis-nucleophilic α-ketoamides with 1,3-bis-electrophilic enals. The obtained oxygen-bridged azepanes can be selectively transformed into optically active azepanone, azepanol or azepanedione derivatives of high synthetic value. This journal is
Reactive spin state dependent enantiospecific photocyclization of axially chiral α-substituted acrylanilides
Ayitou, Anoklase Jean-Luc,Sivaguru
supporting information; experimental part, p. 2568 - 2570 (2011/04/26)
The enantiomeric ratio (e.r.) in the 3,4-dihydroquinolin-2-one photoproduct during 6π-photocyclization of α-substituted axially chiral ortho-tert-butyl-acrylanilides depends on the nature of the reactive spin state (singlet or triplet), where the singlet-
Diastereoselective allylation of α-ketoamides bearing camphor N-tosylpyrazolidinone auxiliary: Efficient synthesis of highly optically active two stereoisomers
Chen, Jung-Hsuan,Venkatesham, Uppala,Lee, Li-Chen,Chen, Kwunmin
, p. 887 - 893 (2007/10/03)
Complementary allylation conditions were developed for the synthesis of both diastereomers of tertiary homoallylic alcohols. Treatment of camphor N-tosylpyrazolidinone derived α-ketoamides with allyltributylstannane afforded both the individual homoallyli
Total Syntheses of (±)-Anchinopeptolide D and (±)-Cycloanchinopeptolide D
Snider, Barry B.,Song, Fengbin,Foxman, Bruce M.
, p. 793 - 800 (2007/10/03)
The first synthesis of (±)-anchinopeptolide D (4) has been accomplished in seven steps in 10% overall yield from octopamine hydrochloride (17), N-(Boc)glycine (16), and 5-amino-2-hydroxypentanoic acid (22). The key step is the aldol dimerization and hemiaminal formation of α-keto amide 26, which gives primarily protected anchinopeptolide D 27 under kinetically controlled conditions. Cycloanchinopeptolide D (31) has been prepared by the unprecedented head-to-head photodimerization of the two hydroxystyrylamides of 4 using the hydrophobic effect in water to force the two side chains into close proximity so that [2 + 2] cycloaddition is faster than trans to cis double bond isomerization. Coupling of amine 21 with pyroglutamic acid affords the naturally occurring tripeptide 35, which had been assigned glutamic acid structure 34.
Electro-organic synthesis 68.1 diastereoselective cathodic reduction of phenylglyoxylic acid attached to chiral auxiliaries
Reufer, Christian,Zielinski, Claudia,Schaefer, Hans Juergen,Froehlich, Roland
, p. 1023 - 1037 (2007/10/03)
Two chiral auxiliaries were attached to phenylglyoxylic acid as amides in 67-70% yield. Cyclic voltammetry of one amide in acetonitrile-pivalic acid (0.117 mol 1-1) shows that it is irreversibly reduced at -0.73 to -1.07 V (vs. Ag/AgCl) dependi