760980-80-1Relevant academic research and scientific papers
A versatile catalyst system for enantioselective synthesis of 2-substituted 1,4-benzodioxanes
Chong, Eugene,Qu, Bo,Zhang, Yongda,Cannone, Zachary P.,Leung, Joyce C.,Tcyrulnikov, Sergei,Nguyen, Khoa D.,Haddad, Nizar,Biswas, Soumik,Hou, Xiaowen,Kaczanowska, Katarzyna,Chwalba, Micha?,Tracz, Andrzej,Czarnocki, Stefan,Song, Jinhua J.,Kozlowski, Marisa C.,Senanayake, Chris H.
, p. 4339 - 4345 (2019/04/17)
We report the synthesis of enantiomerically enriched 1,4-benzodioxanes containing alkyl, aryl, heteroaryl, and/or carbonyl substituents at the 2-position. The starting 1,4-benzodioxines were readily synthesized via ring closing metathesis using an efficient nitro-Grela catalyst at ppm levels. Excellent enantioselectivities of up to 99:1 er were obtained by using the versatile catalyst system [Ir(cod)Cl]2/BIDIME-dimer in the asymmetric hydrogenation of 2-substituted 1,4-benzodioxines. Furthermore, DFT calculations reveal that the selectivity of the process is controlled by the protonation step; and coordinating groups on the substrate may alter the interaction with the catalyst, resulting in a change in the facial selectivity.
Synthesis of unsaturated 1,4-heteroatom-containing benzo-fused heterocycles using a sequential isomerization-ring-closing metathesis strategy
Morgans, Garreth L.,Ngidi, E. Lindani,Madeley, Lee G.,Khanye, Setshaba D.,Michael, Joseph P.,de Koning, Charles B.,van Otterlo, Willem A.L.
experimental part, p. 10650 - 10659 (2010/01/16)
A small library of 1,4-benzodioxins and 4H-1,4-benzoxazines was synthesized from the corresponding bis-allyloxy precursors by way of an initial isomerization to the bis-vinyloxy compounds, followed by a ring-closing metathesis using the second generation Grubbs' catalyst (G2). A related strategy, starting from benzene-1,2-dithiol and 2-mercaptophenol, afforded benzodithiin and 1,4-benzoxathiin, respectively.
Sequential isomerization and ring-closing metathesis: Masked styryl and vinyloxyaryl groups for the synthesis of benzo-fused heterocycles
Van Otterlo, Willem A. L.,Ngidi, E. Lindani,De Koning, Charles B.
, p. 6483 - 6486 (2007/10/03)
The use of an aryl allyl ether and an arylallyl group as masked vinyl ether and 1-propenylphenyl groups for ring-closing metathesis (RCM) leading to the synthesis of benzo-fused heterocycles was demonstrated by using a ruthenium-mediated isomerization followed by a ruthenium-mediated RCM reaction. This resulted in the syntheses of a variety of products including two substituted benzo[1,4]dioxins, a naphtho[2,3-b][1,4]dioxin, a 2H-chromene and a benzo[b]furan.
