309918-73-8Relevant academic research and scientific papers
Silyloxy Amino Alcohol Organocatalyst for Enantioselective 1,3-Dipolar Cycloaddition of Nitrones to α,β-Unsaturated Aldehydes
Otsuki, Teppei,Kumagai, Jun,Kohari, Yoshihito,Okuyama, Yuko,Kwon, Eunsang,Seki, Chigusa,Uwai, Koji,Mawatari, Yasuteru,Kobayashi, Nagao,Iwasa, Tatsuo,Tokiwa, Michio,Takeshita, Mitsuhiro,Maeda, Atushi,Hashimoto, Akihiko,Turuga, Kana,Nakano, Hiroto
supporting information, p. 7292 - 7300 (2015/11/25)
The catalytic activity of a simple amino alcohol that contains a bulky super silyl group [i.e., tris(trimethylsilyl)silyl (TTMSS)] bonded to the oxygen atom at the γ-position along with a primary amine moiety was examined in the enantioselective 1,3-dipolar cycloaddition of nitrones to α,β-unsaturated aldehydes. The organocatalyst successfully provided optically active isoxazolidines in good chemical yields (up to 86 %) with excellent diastereoselectivities (endo/exo, up to 96:4) and enantioselectivities (up to 97 % ee). Furthermore, the obtained isoxazolidines were easily converted into γ-amino diols that contain three contiguous stereogenic centers.
Assessment of non-standard reaction conditions for asymmetric 1,3-dipolar organocatalytic cycloaddition of nitrone with α,β-unsaturated aldehydes
Mojzesová, Melinda,Me?iarová, Mária,Almássy, Ambroz,Marti, Roger,?ebesta, Radovan
, p. 737 - 746 (2015/04/14)
Non-standard experimental conditions can often enhance organocatalytic reactions considerably. The current study explores the effectiveness of a range of non-standard reaction conditions for the asymmetric organocatalytic 1,3-dipolar cycloaddition of a nitrone with α,β-unsaturated aldehydes. The influence of ionic liquids, high-pressure conditions, ultrasound, microwave irradiation and ballmilling was tested as well as the flow process. Because of the low reactivity of the nitrone and unsaturated aldehydes in the 1,3-dipolar cycloaddition, cycloadducts were isolated in only moderate yields from the majority of experiments. However, high diastereo- and enantioselectivities were observed in ionic liquids under solvent-free conditions and in the flow reactor.
Enantioselective 1,3-dipolar cycloadditions of nitrones with unsaturated aldehydes promoted by a recyclable tetraarylphosphonium supported imidazolidinone catalyst
Nie, Xin,Lu, Cuifen,Chen, Zuxing,Yang, Guichun,Nie, Junqi
, p. 171 - 174 (2014/07/21)
The tetraarylphosphonium supported chiral imidazolidinone catalyzes the enantioselective 1,3-dipolar cycloadditions of nitrones and α,β- unsaturated aldehydes to provide isoxazolidine aldehydes in good yields with excellent diastereo- and enantioselectivi
A magnetoclick imidazolidinone nanocatalyst for asymmetric 1,3-dipolar cycloadditions
Pagoti, Sreenivasarao,Dutta, Debasish,Dash, Jyotirmayee
, p. 3532 - 3538 (2014/01/06)
A 1,3-dipolar azide-alkyne cycloaddition has been used to prepare a magnetic nanoparticle immobilized MacMillan catalyst that catalyzes the enantioselective 1,3-dipolar cycloaddition between nitrones and α,β-unsaturated aldehydes. The catalyst can be recovered and recycled for five consecutive runs without any significant loss in yields and diastereo- and enantioselectivities of the isoxazolidines. Copyright
Synthesis and application of a recyclable ionic liquid-supported imidazolidinone catalyst in enantioselective 1,3-dipolar cycloaddition
Shen, Zhi-Liang,Goh, Kau Kiat Kelvin,Wong, Colin Hong An,Loo, Wan-Yi,Yang, Yong-Sheng,Lu, Jun,Loh, Teck-Peng
supporting information; body text, p. 5856 - 5858 (2012/08/14)
The synthesis of recyclable ionic liquid-supported imidazolidinone catalyst I and its application in 1,3-dipolar cycloaddition of nitrone with α,β-unsaturated aldehyde with high performance were described. Most importantly, the catalyst I can be recovered
The highly enantioselective 1,3-dipolar cycloaddition of alkyl glyoxylate-derived nitrones to E-crotonaldehyde catalyzed by hybrid diamines
Weseliński, ?ukasz,S?yk, Edyta,Jurczak, Janusz
experimental part, p. 381 - 384 (2011/03/18)
1,3-Dipolar cycloaddition of alkyl glyoxylate-derived nitrones to E-crotonaldehyde can be catalyzed by hybrid diamines, obtained from (S)-BINAM and l-α-amino acids. The hybrid of (S)-BINAM and l-Phe was found to be the best organocatalyst. Products were o
Hydrazide-catalyzed 1,3-dipolar nitrone cycloadditions
Lemay, Mathieu,Trant, John,Ogilvie, William W.
, p. 11644 - 11655 (2008/03/13)
The triflate salts of cyclic hydrazides function as asymmetric catalysts for the [3+2]cycloadditions of nitrones with α,β-unsaturated aldehydes. The camphor-derived hydrazides show a preference for the exo isomers during these reactions, providing a compliment to other organically catalyzed dipolar cycloadditions. Enantiomeric excesses as high as 93% were realized for the exo isomers, while some endo products were obtained in 94% ee.
