10.1021/acs.joc.9b01119.s003
Yumehiro Manabe
Yumehiro
Manabe
Mitsuharu Uesaka
Mitsuharu
Uesaka
Tomoki Yoneda
Tomoki
Yoneda
Yasuhide Inokuma
Yasuhide
Inokuma
Two-Step Transformation
of Aliphatic Polyketones into
π‑Conjugated Polyimines
American Chemical Society
2019
Two-Step Transformation
ethylene-bridged oligoisopyrazoles
aliphatic polyketones
absorption
Subsequent oxidation
polyimine
stereoselective oxidation
Imine formation
π- conjugation
Aliphatic Polyketones
polydisperse polymers
transformation
ethylene bridge
metal-coordination behaviors
yield
2019-06-25 00:00:00
Dataset
https://acs.figshare.com/articles/dataset/Two-Step_Transformation_of_Aliphatic_Polyketones_into_Conjugated_Polyimines/8427842
The
chemo- and stereo-selective two-step transformation of aliphatic
polyketones composed of 3,3-dimethylpentane-2,4-dione units was achieved
to generate π-conjugated polyimines. Upon treatment with hydrazine,
discrete oligoketones with 4–8 carbonyl groups afforded ethylene-bridged
oligoisopyrazoles in 80–89% yields. These oligoisopyrazoles
underwent stereoselective oxidation at the ethylene bridge to give
fully π-conjugated oligo(isopyrazole-3,5-diyl-trans-vinylene)s
in 73–87% yields. Oxidation of the oligoimines drastically
changed their absorption and metal-coordination behaviors. Finally,
this two-step transformation was applied to polydisperse polymers.
Imine formation proceeded almost quantitatively, even for longer polyketones,
including docosamer. Subsequent oxidation of the polyimines furnished
a virtually insoluble material that showed broad and red-shifted solid-state
absorption over the whole visible region resulting from extended π-conjugation.