26465-78-1Relevant academic research and scientific papers
Asymmetric Hydrogenation of Unfunctionalized Tetrasubstituted Acyclic Olefins
Bachmann, Stephan,Bigler, Raphael,Denmark, Scott E.,Gosselin, Francis,Han, Chong,Hildbrand, Stefan,Mack, Kyle A.,Pfaltz, Andreas,Scalone, Michelangelo,Shen, Jeff,Tosatti, Paolo,Zhang, Haiming
, p. 2844 - 2849 (2020/02/05)
Asymmetric hydrogenation has evolved as one of the most powerful tools to construct stereocenters. However, the asymmetric hydrogenation of unfunctionalized tetrasubstituted acyclic olefins remains the pinnacle of asymmetric synthesis and an unsolved challenge. We report herein the discovery of an iridium catalyst for the first, generally applicable, highly enantio- and diastereoselective hydrogenation of such olefins and the mechanistic insights of the reaction. The power of this chemistry is demonstrated by the successful hydrogenation of a wide variety of electronically and sterically diverse olefins in excellent yield and high enantio- and diastereoselectivity.
Friedel-Crafts alkylation of benzene with 1,2-diphenyl-2-propanol, 1-chloro-2,3-diphenylpropane and 2-methyl-1-phenyl-2-butanol
Khalaf, Ali A.,Awad, Ibrahim M.,El-Emary,El-Aal, H.A.K. Abd
, p. 595 - 600 (2011/08/21)
The alkylation of benzene with 1,2-diphenyl-2-propanol (1) using AlCl 3/CH3NO2 catalyst gave a mixture of 1,2,2- (4) and 1,1,2-triphenylpropane (5) as product alkylates. With 85% H 2SO4 catalyst, the product consisted of E-1,2-diphenylpropene (6) after 2 h of a mixture of 5 and 6 after 18 h. Similar alkylation of benzene with 1-chloro-2,3-diphenylpropane (2) using AlCl 3 catalyst gave a mixture consisting of 4, 5 and 6. Finally, alkylation of benzene with 2-methyl-1-phenyl-2-butanol (3) using AlCl 3/CH3NO2 gave 2-methyl-1,1-diphenylbutane (10) as sole product alkylate. The identities of the products were confirmed spectroscopically and by comparison with unequivocally prepared samples. Mechanisms are proposed to rationalise the observed results.
Formation of cyclopropanes by the reductive coupling of 1,3-dihalides promoted by titanocene(II) species
Takeda, Takeshi,Shimane, Keiko,Fujiwara, Tooru,Tsubouchi, Akira
, p. 290 - 291 (2007/10/03)
The treatment of various 1,3-dihalides including the ones bearing an ester group with the titanocene(II) species produced cyclopropanes in good yields. The reaction of dihalides possessing two secondary halogens proceeded stereoselectively to afford trans
Decarbonylative diarylation reaction of N-tosylated α-amino acids
Seong, Mi Ra,Lee, Hong Jung,Kim, Jae Nyoung
, p. 6219 - 6222 (2007/10/03)
The reaction of various N-tosylated α-amino acids with arenes in the presence of sulfuric acid afforded the corresponding diarylated derivatives in moderate yields, which were generated via decarbonylative arylation followed by Friedel-Crafts reaction of the generated tosylamide derivatives.
