721430-38-2Relevant academic research and scientific papers
Synthesis and immunopotentiating activity of novel isoxazoline functionalized coumarins
Ismail, Tabasum,Shafi, Syed,Singh, Swarn,Sidiq, Tabasum,Khajuria, Anamika,Rouf, Abdul,Yadav, Mahipal,Saikam, Varma,Singh, Parvinder Pal,Alam, Mohammad Sarwar,Islam, Nasarul,Sharma, Kalicharan,Kumar, Halmuthur Mahabalarao Sampath
, p. 90 - 104 (2016)
A novel series (13) of isoxazoline functionalized coumarins was synthesized through 1,3-dipolar cyclization of nitrile oxides with Allylated coumarins. Synthesis of effective and target selective immunostimulators through conjugation of diversely substitu
Asymmetric 1,3-dipolar cycloaddition reactions of nitrile oxides catalyzed by chiral binaphthyldiimine-Ni(II) complexes
Suga, Hiroyuki,Adachi, Yuki,Fujimoto, Kouhei,Furihata, Yasuhisa,Tsuchida, Teruko,Kakehi, Akikazu,Baba, Toshihide
supporting information; experimental part, p. 1099 - 1113 (2009/07/04)
Asymmetric cycloaddition reactions between several nitrile oxides and 3-(2-alkenoyl)-2-oxazolidinones and 2-(2-alkenoyl)-3-pyrazolidinone derivatives were carried out in the presence of chiral binaphthyldiimine (BINIM)-Ni(II) complexes as catalysts. Using (tf)-BENM-4(3,5-xylyl)-2QN-Ni(II) complex (30 mol %), good regioselectivity (4-Me/5-Me = 85:15) along with high enantioselectivity (96% ee) of the 4-Me adduct were obtained for the reaction between isolable 2,4,6-trimethylbenzonitrile oxide and 3-crotonoyl-5,5-dimethyl-2-oxazolidinone. Substituted and unsubstituted benzonitrile oxides and aliphatic nitrile oxides, which were generated from the corresponding hydroximoyl chloride in the presence of MS 4A, were reacted with 3-crotonoyl-5,5-dimethyl-2-oxazolidinone, 5,5-dimethyl-3-(2-pentenoyl)-2-oxazolidinone, 5,5-dimethy-3-[3-(ethoxycarbonyl) propenoyl]-2-oxazolidinone, 1-benzyl-2-crotonoyl-5,5-dimethyl-3-pyrazolidinone, and 1-ben-zyl-2-[3-(ethoxycarbonyl)propenoyl]-5,5-dimethy-3-pyrazolidinone in the presence of (K)-BENM-4Ph-2QN-Ni(II) or (tf)-BENM-4(3,5-xylyl)-2QN-Ni(II) complexes (10-30 mol %) as catalysts to give the corresponding cycloadducts in high yields, with high regioselectively (4-R/5-R = 85:15-99:1) and with moderate to high enantioselectivities (42-95% ee) of the 4-R adducts. Higher enantioselectivities and regioselectivities were obtained for the reactions using pyrazolidinone derivatives as the dipolarophiles. For the cycloadditions of 2-(2-alkenoyl)-1-benzyl-5,5-dimethyl-3-pyrazolidinones catalyzed by (tf)-BENM-4(3,5-xylyl)-2QN-Ni(II) complex (30 mol %), the enantioselectivity varied from 75% to 95% ee. The reactions between several nitrile oxides and 2-acryloyl-1-benzyl-5,5-dimethyl-3-pyrazolidinone in the presence of (R)-BINIM-4(3,5-xylyl)-2QN-Ni(II) complex (10 mol %) resulted in enantioselectivities (79-91% ee) that exceed those of previously reported enantioselective cycloadditions of acrylic acid derivatives. Furthermore, studies using a molecular modeling program using PM3 calculations were carried out to gain insight into the mechanisms of the asymmetric induction. 2009 American Chemical Society.
Preparation of novel N-sulfonylated (S,S)-2,3-diaminosuccinate-type chiral auxiliaries and application to an asymmetric 1,3-dipolar cycloaddition reaction of nitrile oxides to allyl alcohol
Serizawa, Masakazu,Ukaji, Yutaka,Inomata, Katsuhiko
, p. 3075 - 3083 (2007/10/03)
Novel N-sulfonylated (S,S)-2,3-diaminosuccinate-type chiral auxiliaries, which have the tartaric acid-like framework with a sulfonamide group instead of a hydroxyl group, were synthesized from l-aspartic acid. The synthesized (S,S)-2,3-diaminosuccinate de
Asymmetric 1,3-dipolar cycloaddition of nitrile oxides generated in situ by direct oxidation of aldoximes
Tsuji, Masamichi,Ukaji, Yutaka,Inomata, Katsuhiko
, p. 1112 - 1113 (2007/10/03)
The asymmetric 1,3-dipolar cycloaddition of nitrile oxides, generated in situ from aldoximes by direct oxidation with tert-butyl hypochlorite, to 2-propen-1-ol was achieved by utilizing diisopropyl (R,R)-tartrate as a chiral auxiliary to afford the corresponding (R)-2-isoxazolines with high enantioselectivity up to 96% ee.
Catalytic asymmetric 1,3-dipolar cycloaddition of nitrile oxides to an achiral allyl alcohol utilizing diisopropyl tartrate as a chiral auxiliary
Shimizu, Makoto,Ukaji, Yutaka,Inomata, Katsuhiko
, p. 455 - 456 (2007/10/03)
The catalytic asymmetric 1,3-dipolar cycloaddition of nitrile oxides to an achiral allyl alcohol was achieved by the use of a catalytic amount of diisopropyl (R,R)-tartrate as a chiral auxiliary to afford the corresponding (R)-2-isoxazolines with high enantioselectivity. In order to realize reproducible higher stereoselection, the addition of a small amount of ethereal compound such as 1,4-dioxane was crucial.
