62322-07-0Relevant academic research and scientific papers
Kinetic Resolution and Dynamic Kinetic Resolution of Chromene by Rhodium-Catalyzed Asymmetric Hydroarylation
Yang, Qingjing,Wang, Yanbo,Luo, Shihui,Wang, Jun (Joelle)
supporting information, p. 5343 - 5347 (2019/03/21)
A highly efficient kinetic resolution and dynamic kinetic resolution of chromene is reported for the first time and they procced by a rhodium-catalyzed asymmetric hydroarylation pathway. This new approach offers versatile access to various chiral 2,3-diaryl-chromanes containing vicinal stereogenic centers, as well as the recovered chiral flavenes, in high yields with excellent ee values (s factor up to 532). Particularly noteworthy is that this strategy can be further extended to the establishment of a dynamic version of the kinetic resolution of chromene acetals and allows complete access to chiral isoflavanes and α-aryl hydrocoumarins.
Organocatalytic asymmetric Michael/hemiacetalization/acyl transfer reaction of α-nitroketones with o-hydroxycinnamaldehydes: Synthesis of 2,4-disubstituted chromans
Maity, Rajendra,Pan, Subhas Chandra
supporting information, p. 1598 - 1608 (2018/03/08)
An organocatalytic asymmetric cascade Michael/hemiketalization/acyl transfer reaction between o-hydroxycinnamaldehydes and α-nitroketones is developed. Prolinol TMS ether catalyst in combination with benzoic acid was found to be the most effective for this reaction which proceeds through an equilibrium of lactols to provide a single diastereomer of enantiopure 2,4-disubstituted chromans.
Trimethylsilyl iodide mediated one-pot synthesis of 2-allyl-2H-chromenes
Padhi, Birakishore,Reddy, D. Srinivas,Mohapatra, Debendra K.
, p. 542 - 547 (2015/01/30)
A new and efficient metal-free trimethylsilyl iodide (TMSI) catalyzed one-pot synthesis of 2-allyl-2H-chromenes has been developed that takes place under mild conditions. The synthesis proceeds through a Wittig reaction by using (triphenylphosphoranylidene)acetaldehyde to form an ohydroxycinnamaldehyde derivative followed by a tandem isomerization and C-O and C-C bond-forming reactions. The procedure was carried out at room temperature in the presence of 20 mol-% of TMSI and allyltrimethylsilane in tetrahydrofuran (THF) and provided the 2-allyl-2H-chromenes in good to excellent yields.
A metal-free one-pot cascade synthesis of highly functionalized biaryl-2-carbaldehydes
Challa, Chandrasekhar,Vellekkatt, Jamsheena,Ravindran, Jaice,Lankalapalli, Ravi S.
supporting information, p. 8588 - 8592 (2014/12/11)
A metal-free one-pot cascade annulation of acyclic substrates dienaminodioate, cinnamaldehydes and allyl amine was achieved for the synthesis of polyfunctional biaryl-2-carbaldehydes. The reaction proceeds at room temperature by a trifluoroacetic acid mediated Diels-Alder pathway. Synthetic applications of the resulting biaryl-2-carbaldehyde have been demonstrated by conversion into an array of diverse molecules with biological and materials chemistry relevance. The present work offers a complementary route to the existing metal mediated cross-coupling methods for the preparation of biaryls.
