1101174-62-2Relevant academic research and scientific papers
A novel and environmental friendly synthetic route for hydroxypyrrolidines using zeolites
Fan,Chuah,Jaenicke, Stephan
, p. 103 - 114 (2018/12/13)
A critical step in the synthesis of the hydroxypyrrolidines, 1,4-dideoxy-1,4-imino-L-lyxitol and 1,4-dideoxy-1,4-imino-D-lyxitol, from the corresponding D-sugars is the synthesis of O-methyl 2,3-O-isopropylidenepentofuranoses. Instead of applying homogeneous catalysis process with conventional inorganic acid catalysts like HCl and HClO4, it was found that heterogeneous catalysis using zeolites could be used for the one-pot synthesis of O-methyl 2,3-O-isopropylidenepentofuranoses directly from D-sugars, MeOH and acetone at mild condition. The best catalyst was H-beta zeolite containing a Si/Al molar ratio of 150, where a yield of >83% was obtained. The overall yields of the five-step procedure to 1,4-dideoxy-1,4-imino-L-lyxitol and 1,4-dideoxy-1,4-imino-D-lyxitol were 57% and 50%, respectively. This synthetic procedure has several advantages such as competitive overall yield, reduced number of steps, and mild reaction conditions. Furthermore, the zeolite catalyst can be easily recovered from the reaction mixture and reused with no loss of activity.
Pyrrolidine-Based P,O Ligands from Carbohydrates: Easily Accessible and Modular Ligands for the Ir-Catalyzed Asymmetric Hydrogenation of Minimally Functionalized Olefins
Elías-Rodríguez, Pilar,Borràs, Carlota,Carmona, Ana T.,Faiges, Jorge,Robina, Inmaculada,Pàmies, Oscar,Diéguez, Montserrat
, p. 5414 - 5424 (2018/12/11)
The potential of P,O-iminosugar based ligands in the Ir-catalyzed asymmetric hydrogenation of minimally functionalized olefins is presented. These new ligands were prepared from easily available carbohydrates (D-mannose, D-ribose and D-arabinose). The stereochemical and polyfunctional diversity of carbohydrates allowed the modulation of the ligands, both from their electronic properties and the rigidity of their backbone. High enantioselectivities (ee’s up to 99 %) can be reached in the hydrogenation of selected tri- and disubstituted substrates.
METHODS FOR THE PREPARATION OF ALKENYLAMINES, CYCLIC CARBAMATES OR DITHIOCARBAMATES, AND AMINOALCOHOLS OR AMINOTHIOLS
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Page/Page column 46, (2010/04/28)
A method for preparing an alkenylamine, or a salt, solvate or hydrate thereof, is disclosed. The method comprises reacting a alogen-substituted cyclic acetal or a derivative thereof under particular conditions to provide the alkenylamine, which may be optionally converted into a salt, solvate or hydrate thereof. A method for preparing a cyclic carbamate or cyclic dithiocarbamate, or a salt, solvate or hydrate thereof, is also disclosed. The method comprises reacting an alkenylamine under particular conditions to provide the cyclic carbamate or cyclic dithiocarbamate, which may be optionally converted into a salt, solvate or hydrate thereof. A method for preparing a 1,2-aminoalcohol or 1,2-aminothiol, or a salt, solvate or hydrate thereof, is also disclosed. The method comprises forming a cyclic carbamate or cyclic dithiocarbamate from an alkenylamine, and deprotecting the cyclic carbamate or cyclic dithiocarbamate to provide the 1,2-aminoalcohol or 1,2-aminothiol, which may optionally be converted into a salt, solvate or hydrate thereof.
Total synthesis without protecting groups: Pyrrolidines and cyclic carbamates
Dangerfield, Emma M.,Timmer, Mattie S. M.,Stocker, Bridget L.
supporting information; body text, p. 535 - 538 (2009/08/07)
(Chemical Equation Presented) A protecting group free synthesis of 2,3-cis substituted hydroxypyrrolidines is reported. Two novel reaction methodologies allow for the stereoselective formation of cyclic carbamates from olefinic amines, and the formation o
