The electrochemicalreduction on Hg cathode of a dropping solution of phenacyl bromides in dry acetone-LiClO4 yields 4-aryl-2-methylfurans and acetophenones. In this process the acetone plays a dual role, as solvent and reagent.
Suzuki–Miyaura cross-coupling reaction of 1,2-oxaborol-2(5H)-ols with carboxylic anhydrides: a new method to furans
作者:Tao Yu、Xin-Yan Wu、Jun Yang
DOI:10.1016/j.tetlet.2014.05.106
日期:2014.7
construct furans via a Suzuki–Miyaura cross-coupling reaction of 1,2-oxaborol-2(5H)-ols with carboxylicanhydrides. In the presence of Pd(OAc)2/PCy3, the multi-substituted alkenylboron compounds could couple with anhydrides to obtain furans in moderate-to-good yields. The addition of bases promoted the coupling reaction, and the plausible reaction mechanism was proposed.
A three-step, single purification procedure has been developed for the concise synthesis of substituted furans from arylacyl bromides. (C) 2014 Elsevier Ltd. All rights reserved.
Optical film, and polarizing plate and liquid crystal display device using the same
申请人:Nagai Michio
公开号:US20070065601A1
公开(公告)日:2007-03-22
An optical film comprising an optically anisotropic layer including a liquid crystalline compound, wherein the optically anisotropic layer satisfies the following formulae:
Re
(450)/
Re
(650)<1.25 Formula (1):
wherein Re(450) and Re(650) are in-plane retardation values (unit: nm) of the optically anisotropic layer at wavelengths of 450 nm and 650 nm, respectively;
0.09<
Re
—
m
(550)/
d
Formula (2):
wherein Re_m(550) is an in-plane retardation value (unit: nm) of a uniaxial alignment layer in which the director of the liquid crystalline compound is aligned to be parallel in the plane at a wavelength of 550 nm, and d is the thickness of the uniaxial alignment layer (unit: nm).
Compound ,Composition And Thin Film
申请人:Takahashi Makoto
公开号:US20080064879A1
公开(公告)日:2008-03-13
A liquid-crystalline compound of the following formula:
wherein Y
11
, Y
12
and Y
13
are methine or N; L
1
, L
2
and L
3
are single bond or divalent group; H
1
, H
2
and H
3
are formula (DI-A) or (DI-B); YA
1
, YA
2
, YB
1
and YB
2
are methine or N; XA and XB are O, S, etc.; R
1
, R
2
and R
3
are -(-L
21
-Q
2
)
n1
-L
22
-L
23
-Q
1
; L
21
is single bond or divalent group; Q
2
is cyclic divalent group; n1 is 0-4; L
22
is —O—, —O—CO—, etc; L
23
is —O—, —S—, etc.; Q
1
is polymerizable group or H.