We disclose a novel high yielding and highly enantioselective chiral calcium VAPOL phosphate-catalyzed chlorination of 3-substituted oxindoles with N-chlorosuccinimide (NCS). The reaction conditions are also shown to be effective for the catalytic enantioselective Michael addition of 3-aryloxindoles to methyl vinyl ketone.
Chiral
supramolecular assembly can provide a powerful strategy
for developing circularly polarized luminescence (CPL)-active materials
by forming helices or superhelices into single or multiple components.
Herein, we chose three achiral liquid crystal polymers (LC-P1/P2/P3) and chiral binaphthyl-based inducers (
R/S
-M) with anchored dihedral angles
to construct chiral co-assemblies and explore the induced CPL behavior
from pyrenyl (Py) emitters in achiral LC polymers through the regulation
of helical nanofibers during the supramolecular co-assembly process.
Most interestingly, chiral co-assembly (
R/S-
M)
0.1
-(P3)
0.9
emitted an inverted blue-colored
CPL signal during thermal annealing treatment at the glass transition
temperature due to the flexible main chain of the LC polymer (LC-P3). The strongest blue-colored CPL emission for the (
R/S-
M)
0.1
-(P3)
0.9
spin-coated
film (λem = 455 nm, |g
em| = 6.47 × 10–2, ΦF = 48.5%)
could be detected by using thermal annealing treatment at 105 °C.
[reaction, structure: see text] Pd-catalyzed asymmetric allylic alkylation of dienyl acetates 1 and amination of allyl acetates 2 provides the corresponding chiral products in high regio- and enantioselectivities using 1,1'-P,N-ferrocenes L1a and L2d as ligands, respectively.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.