29123-91-9Relevant academic research and scientific papers
Catalytic Regioselective Isomerization of 2,2-Disubstituted Oxetanes to Homoallylic Alcohols
Cabré, Albert,Lledós, Agustí,Rafael, Sergi,Riera, Antoni,Sciortino, Giuseppe,Ujaque, Gregori,Verdaguer, Xavier
, p. 7521 - 7527 (2020/03/24)
The selective isomerization of strained heterocyclic compounds is an important tool in organic synthesis. An unprecedented regioselective isomerization of 2,2-disubstituted oxetanes into homoallylic alcohols is described. The use of tris(pentafluorophenyl
Rhodium-Catalyzed Diverse Arylation of 2,5-Dihydrofuran: Controllable Divergent Synthesis via Four Pathways
Dou, Xiaowei,Hayashi, Tamio,Lu, Tao,Xing, Junhao,Ye, Bihai,Zhu, Wanjiang
, p. 2958 - 2963 (2020/03/23)
The rhodium-catalyzed controllable diverse arylation of 2,5-dihydrofuran with arylboronic acids is reported. By fine-tuning of the reaction conditions, four different ring-opening or oxidative arylation pathways are controlled in the rhodium-catalyzed ary
Copper-catalyzed enantioselective 1,2-borylation of 1,3-dienes
Liu, Yangbin,Fiorito, Daniele,Mazet, Clément
, p. 5284 - 5288 (2018/06/21)
A highly enantioselective Cu-catalyzed borylation of 2-substituted 1,3-dienes is reported. The use of a chiral phosphanamine ligand is essential in achieving high chemo-, regio-, diastereo- and enantioselectivity. It provides access to a variety of homoallylic boronates in consistently high yield and enantiomeric excess with 2-aryl and 2-heteroaryl 1,3-dienes as well as sterically demanding 2-alkyl 1,3-dienes. Preliminary investigations based on a non-linear effect study point to a mechanism involving more than one metal center.
Enantioselective Small Molecule Synthesis by Carbon Dioxide Fixation using a Dual Br?nsted Acid/Base Organocatalyst
Vara, Brandon A.,Struble, Thomas J.,Wang, Weiwei,Dobish, Mark C.,Johnston, Jeffrey N.
supporting information, p. 7302 - 7305 (2015/06/30)
Carbon dioxide exhibits many of the qualities of an ideal reagent: it is nontoxic, plentiful, and inexpensive. Unlike other gaseous reagents, however, it has found limited use in enantioselective synthesis. Moreover, unprecedented is a tool that merges on
Helical triskelion monophosphites as ligands in asymmetric catalysis
Reetz, Manfred T.,Guo, Hongchao,Jun-An, Ma.,Goddard, Richard,Mynott, Richard J.
supporting information; experimental part, p. 4136 - 4142 (2009/09/05)
Members of a new family of chiral triskelion P ligands, namely helical C3-symmetric monophos- phites P(OR)3, have been prepared in two steps Dy monoacylation of (R)- or (S)-1,1'-binaphthyl-2,2'-diol (BINOL) or diphenol using a carboxylic acid chloride followed Dy PCl3 phosphorylation. The most sterically hindered member of these monophosphites, derived from the compound accessible by monoacylation of BINOL using adamantane carboxylic acid chloride, has been characterized by X-ray crystallography and NMR spectroscopy as a single well-defined compound. It exists exclusively in the syn conformation, with a propeller-like (twisted) geometry resulting in helicity. Upon utilization of(R)- or (S)-BINOL in the two-step synthesis, the helicity proves to be P or M, respectively. When used as ligands in the Rh-catalyzed asymmetri c hydrogenation of prochiral homoallylic alcohols, these bulky helical ligands lead to respectable enantioselectivities (79-98percent ee). In contrast, the less sterically congested and more flexible BINOL-derived phenyl analogue exists in several conformeric forms, even in the crystal, and this leads to poor enantioselectivity in the model reactions (ee = 32percent). For the purpose of structural comparison, the analogous monophosphites derived from diphenol were also prepared and characterized. These compounds, again in contrast to the BINOL-derived adamantyl derivatives, occur in several different conformeric states.
Regioselective Heck arylation of unsaturated alcohols by palladium catalysis in ionic liquid
Mo, Jun,Xu, Lijin,Ruan, Jiwu,Liu, Shifang,Xiao, Jianliang
, p. 3591 - 3593 (2008/09/20)
In contrast to almost all of the known examples of Heck arylation of unsaturated alcohols, which yield predominately β-arylated products, arylation under the Pd-DPPP catalysis in ionic liquid leads preferentially to aryl substitution at the α carbon, prov
Practical carbonyl-ene reactions of α-methylstyrenes with paraformaldehyde promoted by a combined system of boron trifluoride and molecular sieves 4A
Okachi, Takahiro,Fujimoto, Katsuhiko,Onaka, Makoto
, p. 1667 - 1669 (2007/10/03)
Matrix presented A combined system of boron trifluoride and molecular sieves is an efficient promoter for the carbonyl-ene reaction of a-methylsyrenes with paraformaldehyde. The coexistence of BF3-OEt2 and molecular sieves 4A is esse
An efficient synthesis of enantiomerically pure 2-[(2R)-arylmorpholin- 2-yl]ethanols, key intermediates of tachykinin receptor antagonist
Nishi, Takahide,Ishibashi, Koki,Nakajima, Katsuyoshi,Iio, Yukiko,Fukazawa, Tetsuya
, p. 3251 - 3262 (2007/10/03)
We report herein an efficient and practical synthetic method for the preparation of enantiomerically pure 2[(2R)-arylmorpholin-2-yl]ethanols 1a- d, key intermediates of tachykinin receptor antagonist. Sharpless catalytic asymmetric dihydroxylation of 4a-d was employed to introduce the required absolute stereochemistry, and cyclization of 7a-d was accomplished by the Mitsunobu reaction.
