68258-25-3Relevant academic research and scientific papers
Tandem arylation and regioselective allylic etherification of 2,3-allenol: Via Pd/B cooperative catalysis
Li, Hongfang,Li, Tao,Hsueh, Yu Jen,Wu, Xue,Xu, Feng,Zhang, Yong Jian
, p. 8075 - 8078 (2019)
An efficient method for the construction of arylated allylic ethers was developed via three-component tandem arylation and allylic etherification of 2,3-allenol with aryl iodides and alcohols. In the cooperative catalytic system of a palladium complex and triethylborane, the process allows rapid access to functionalized 1-arylvinylated 1,2-diol derivatives in good to high yields with complete branch-selectivities. The synthetic utility of the present process was demonstrated by the late-stage functionalization of a drug molecule, the gram-scale synthesis and the elaboration of the products.
Hydrazinium carbazate-H2O2: An ideal combination for diimide reduction of base-sensitive unsaturated peroxides
Singh, Chandan,Singh, Ajit Shankar,Naikade, Niraj Krishna,Verma, Ved Prakash,Hassam, Mohammad,Gupta, Nitin,Pandey, Shilpi
experimental part, p. 1014 - 1022 (2010/06/16)
The utility of a hydrazinium carbazate (N2H3COON 2H5) and H2O2 combination for the double bond reduction of base-sensitive unsaturated 1,2,4-trioxanes, 1,2,4-trioxepanes, and their precursors β-andγ-hydroxyhydroperoxides is presented. The method is superior to the conventional diimide reduction using N2H4H2O-H2O2 and catalytic hydrogenation.
[1,2]-Wittig rearrangement of (benzyloxy)acetamides
Hameury, Thomas,Guillemont, Jér?me,Van Hijfte, Luc,Bellosta, Véronique,Cossy, Janine
scheme or table, p. 2345 - 2347 (2009/05/27)
[1,2]-Wittig rearrangement of (benzyloxy)acetamides can lead to substituted α-hydroxyamides in good yields and good diastereoselectivity. Georg Thieme Verlag Stuttgart.
A Catalytic Asymmetric Synthesis of N-Boc-β-Methylphenylalanines
Pasto, Mireia,Moyano, Albert,Pericas, Miquel A.,Riera, Antoni
, p. 8425 - 8431 (2007/10/03)
An efficient, stereodivergent, and enantioselective synthesis of the syn and anti diastereomers of N-Boc-β-methylphenylalanine has been developed. Starting from enantiomerically pure (2S,3S)-2,3-epoxy-3-phenyl-1-propanol, a three-step sequence, consisting of the oxidation of the primary alcohol up to the carboxyl stage, ring opening of the epoxy acid with Me2CuCNLi2, and esterification of the resulting hydroxy acid with methyl iodide, leads to the hydroxy ester anti-W, which has been converted in a stereodivergent manner into both the (2S,3R) and the (2R,3R) diastereomers of N-Boc-β-methylphenylalanine, syn-1 and anti-1, respectively. Activation of the secondary hydroxy group in anti-10 as a mesylate, followed by nucleophilic displacement with sodium azide, hydrogenolysis with simultaneous protection of the amino group, and saponification with LiOH, affords syn-1. The same reaction sequence applied to syn-10, obtained in turn by Mitsunobu reaction of anti-10 with p-nitrobenzoic acid followed by the hydrolysis of the resulting p-nitrobenzoate, leads to anti-1. Both products have been obtained with ≥99% enantiomeric excess.
Enantioselective syntheses of 2-arylpropanoic acid non-steroidal antiinflammatory drugs and related compounds
Hamon, David P.G.,Massy-Westropp, Ralph A.,Newton, Josephine L.
, p. 12645 - 12660 (2007/10/02)
(S)-2-[4′-(2″-Methylpropyl)phenylpropanoic acid (ibuprofen) and (S)-2-(3′-benzoylphenyl)propanoic acid (ketoprofen) have been synthesised in high enantiomeric excess. Control of stereochemistry was achieved by a combination of Sharpless epoxidalion followed by catalytic hydrogenolysis of the introduced benzylic epoxide oxygen bond. Also, the coupling of organic compounds in the presence of palladium with enantiopure 2-(3-iodophenyl)propanoic and 2-(4-iodophenyl)propanoic acids, prepared by the methodology above, is a general method for the synthesis of optically active arylpropanoic acids.
Practical hydroxymethylation of aldehydes and ketones via pinacol cross-coupling reactions with paraformaldehyde
Park, Jeonghan,Pedersen, Steven F.
, p. 2069 - 2080 (2007/10/02)
A general and practical method for the direct hydroxymethylation of aldehydes and ketones via pinacol cross-coupling with paraformaldehyde is described. The reaction is promoted by vanadium(II) ions which are conveniently generated from the reduction of VCl3(THF)3 with zinc dust. Excellent yields of terminal diols are obtained and stereoselective coupling is observed with some chiral aldehydes and ketones.
Uncatalyzed and Chorismate Mutase Catalyzed Claisen Rearrangement of (Z)-9-Methylchorismic Acid
Lesuisse, Dominique,Berchtold, Glenn A.
, p. 4992 - 4997 (2007/10/02)
A synthesis of (-)- and (+/-)-(Z)-9-methylchorismic acid (3) is reported.The half-life for the uncatalyzed Claisen rearrangement of (+/-)-3 in H2O (pH 7.5, 30 deg C) is 5.7 h.Chorismate analogue (-)-3 was a modest substrate for chorismate mutase (chorismate mutase-prephenate dehydrogenase from E. coli): Km = 4.0 mM, kcat./kuncat. = 4.2*104.It was established that the enzyme-catalyzed Claisen rearrangement of (-)-3 proceeds through a chairlike transition state in similar fashion to the chorismate mutase catalyzed rearrangement of (-)-chorismic acid (1).
REGIO- AND STEREOSELECTIVE RING OPENING OF EPOXY ALCOHOLS WITH ORGANOALUMINIUM COMPOUNDS LEADING TO 1,2-DIOLS
Suzuki, Toshifumi,Saimoto, Hiroyuki,Tomioka, Hiroki,Oshima, Koichiro,Nozaki, Hitosi
, p. 3597 - 3600 (2007/10/02)
Introduction of alkyl, alkynyl group, or hydride occurs regioselectively at the 3 position of the epoxy alcohols with inversion of the configuration upon treatment with organoaluminium reagents to produce vic-diols.
