Ma, Hao published the artcileDesign and Synthesis of Bridging Chiral p-t-Butylcalix[4]arene Tetrahydroisoquinolines and Their Application in Henry Reaction as Chiral Organocatalysts, Application In Synthesis of 21286-54-4, the publication is ChemistrySelect (2019), 4(15), 4642-4646, database is CAplus.
A pair of bridging chiral p-t-butylcalix[4]arenes (2a and 2b) (were) synthesized from 1 through homologous anionic ortho-Fries rearrangement, and optically resolved with (1S)-(+)-10-camphorsulfonyl chloride as chiral auxiliary. Bridging chiral p-t-butylcalix[4]arene tetrahydroisoquinolines (9a and 9b) as chiral organocatalysts for Henry reaction were designed and synthesized through the structural modification of 2a and 2b, resp. Compared to the catalytic enantioselectivity of the unmodified tertiary amine (4b: â?% ee and 63% yield), those of the tetrahydroisoquinoline derivatives (9b: up to 13.4% ee and 96% yield) were distinctly enhanced. Although the increase magnitude of the catalytic ee is not remarkable, these catalytic results prove that the conformation inversion of calix[4]arene skeleton and the rotational freedom reduction of catalytic amine group indeed bring beneficial effects on the catalytic stereoselectivity.
ChemistrySelect published new progress about 21286-54-4. 21286-54-4 belongs to chlorides-buliding-blocks, auxiliary class Chiral,Chloride,Sulfonyl chlorides,Aliphatic cyclic hydrocarbon,Ketone, name is ((1S,4R)-7,7-Dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonyl chloride, and the molecular formula is C10H15ClO3S, Application In Synthesis of 21286-54-4.
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