Divergent Rearrangements of Cyclopropyl-Substituted Fluoroepoxides Involving C–F Bond Cleavage and Formation
作者:Tao Luo、Rui Zhang、Wei Zhang、Xiao Shen、Teruo Umemoto、Jinbo Hu
DOI:10.1021/ol403644n
日期:2014.2.7
Unprecedented divergent rearrangements of cyclopropyl-substituted fluoroepoxides are reported. In the presence of a catalytic amount of benzoic acid, cyclopropyl-substituted fluoroepoxides efficiently undergo 1,5-fluorine migration. However, when the fluoroepoxides are heated with K2CO3 at 60 °C, 1,2-fluorine migration occurs. The 1,5-fluorine migration is believed to proceed via a carbocation intermediate
据报道,环丙基取代的氟环氧化物发生了前所未有的发散重排。在催化量的苯甲酸存在下,环丙基取代的氟环氧化物有效地经历了1,5-氟的迁移。然而,当将氟环氧化物与K 2 CO 3在60°C下加热时,会发生1,2-氟迁移。据信1,5-氟迁移通过碳正离子中间体进行,而1,2-氟迁移可能涉及紧密的离子对中间体或通过协同过程进行。
Solvent-free mechanochemical preparation of phosphonium salts, phosphorus ylides, and olefins
申请人:Iowa State University Research Foundation, Inc.
公开号:US20030176740A1
公开(公告)日:2003-09-18
The present invention provides a method of preparing a phosphonium salt of the formula [R
1
R
2
R
3
P—CR
4
R
5
R
6
]X, comprising ball-milling a phosphine of the formula R
1
R
2
R
3
P with a compound of the formula XCR
4
R
5
R
6
; a method of preparing a phosphorus ylide of the formula R
1
R
2
R
3
P═CR
4
R
5
, comprising ball-milling a phosphonium salt of the formula [R
1
R
2
R
3
P—HCR
4
R
5
]X in the presence of a base; and a method of preparing an olefin of the formula R
4
R
5
C═CR
7
H or R
4
R
5
C═CR
7
R
8
, comprising ball-milling a phosphorus ylide of the formula R
1
R
2
R
3
P═CR
4
R
5
with a compound of the formula R
7
C(O)H or R
7
C(O)R
8
. The inventive method produces phosphonium salts and phosphorus ylides by mechanical processing solid reagents under solvent-free conditions. The advantages of the present invention over conventional solution methods, include: (1) extremely high selectivity; (2) high yields; (3) low processing temperatures; (4) simple and scalable reactions using commercially available equipment; and (5) the complete elimination of solvents from the reaction.
There is provided an electroluminescent composition. The composition includes a material having Formula I
In Formula I: R
1
is the same or different at each occurrence and is selected from D, alkyl, alkoxy, silyl, and siloxane, or adjacent R
1
groups may be joined together to form a 5- or 6-membered aliphatic ring; Ar
1
and Ar
2
are the same or different and are aryl groups; a is an integer from 0 to 6; b is an integer from 0 to 2; and c is an integer from 0 to 3.
trans→cis Photoisomerization of 1-styrylnaphthalene and its 4′-bromo- and 4′-chloro-derivatives. A fluorimetric and laser flash photolytic study
作者:Fausto Elisei、Ugo Mazzucato、Helmut Görner
DOI:10.1039/f19898501469
日期:——
The trans→cisphotoisomerization of 1-styrylnaphthalene (1-StN) and two para-halogen-substituted derivatives (Cl- and Br-1-StN) have been studied in solution by laserflash photolysis and by fluorimetric and photochemical methods. Measurements of the fluorescence lifetime (τF) and quantum yield (ϕF), the corresponding triplet data (τT, ϕT), and the trans→cisphotoisomerization quantum yield (ϕt→c)
PHOTOACTIVE COMPOSITION AND ELECTRONIC DEVICE MADE WITH THE COMPOSITION
申请人:Gao Weiying
公开号:US20130126852A1
公开(公告)日:2013-05-23
There is provided a photoactive composition including: (a) 50-99 wt % based on the total weight of the photoactive composition, of at least one host material having a HOMO energy level; (b) 1-10 wt % based on the total weight of the photoactive composition, of an emissive dopant; and (c) 0.1 to 10 wt % based on the total weight of the photoactive composition, of a non-emissive dopant. The non-emissive dopant is an organometallic iridium complex that has a HOMO energy level shallower than the HOMO energy level of the host.