Remote Arylative Substitution of Alkenes Possessing an Acetoxy Group via β‐Acetoxy Elimination

2021 ◽  
Author(s):  
Kazuma Muto ◽  
Takaaki Kumagai ◽  
Fumitoshi Kakiuchi ◽  
Takuya Kochi
Keyword(s):  
Acetoxy Group

Participation of the oxygen-containing substituent in alkaline saponification of 3,4a-disubstituted 4,4-dimethyl-5,6β-epoxy-A-homo-5β-cholestane derivatives

1986 ◽  
Vol 51 (4) ◽  
pp. 930-936 ◽  
Author(s):  
Helena Velgová
Keyword(s):  
Hydroxy Group ◽  
Acetoxy Group ◽  
Epoxide Ring ◽  
Main Component ◽  
Hydroxy Groups

Alkaline saponification of the 3-acetoxy group in 3,4a-disubstituted 4,4-dimethyl-5,6β-epoxy-A-homo-5βcholestane derivatives I-VI was studied. It was found that the 3α- and 4aα-hydroxy groups participated in the cleavage of the 5β,6β-epoxide ring in the derivatives II-IV: the 5(O)n participation by the 3α-hydroxy group (the derivatives III and IV) led to formation of the transannular 3α,5α-epoxides XII and XIV whereas the participation by the 4aα-hydroxy group (the derivatives II and IV) gave rise to the 4aα,5α-epoxides IX and XV. The 5(O)n participation by the 3α-hydroxy group predominated over the preparation by the 4aα-hydroxy group. In the case of the 4a-keto epoxides V and VI the retroaldol-aldol type isomerization led to formation of 3β-hydroxy-4,4-dimethyl-5,6β-epoxy-A-homo-5β-cholestan-4a-one as the main component of the equilibration mixtures.

Approaches to Cyclopropa-Fused Quinones. The Synthesis and Photolysis of Some 4,9-Disubstituted 3,3-Dimethyl-3H-benz[f]indazoles

2003 ◽  
Vol 56 (9) ◽  
pp. 903 ◽  
Author(s):  
Gavin E. Collis ◽  
Dieter Wege
Keyword(s):  
Low Temperature ◽  
Functional Group ◽  
Alkoxy Group ◽  
The Other ◽  
Acetoxy Group

Addition of 2-diazopropane to 1,4-naphthoquinone at low temperature, followed by in situ enolization and acetylation or silylation gave 3,3-dimethyl-1H-benz[f]indazol-4,9-diyl diacetate and 3,3-dimethyl-9-(t-butyl-dimethylsilyloxy)-1H-benz[f]indazol-4-ol, respectively. Functional group manipulation of the latter compound provided a number of other 4,9-disubstituted 3,3-dimethyl-3H-benz[f]indazoles. Irradiation of the diacetate led to clean extrusion of nitrogen to give the naphtho[b]cycloproparene and an alkene. Attempts to elaborate the cycloproparene into the derived cyclopropanaphthoquinone were unsuccessful. Of the other 4,9-disubstituted 3,3-dimethyl-3H-benz[f]indazoles examined, only the compound possessing an acetoxy group at C9 was photoactive, and afforded the expected cycloproparene and alkene. Compounds bearing a hydroxy or alkoxy group at C9 were photochemically inert.

Free-radical acetoxy group migration: an E.P.R. spectral study

1971 ◽  
Vol 24 (10) ◽  
pp. 2099 ◽  
Author(s):  
ALJ Beckwith ◽  
PK Tindal
Keyword(s):  
Free Radical ◽  
Spectral Data ◽  
Spectral Study ◽  
Hyperfine Splitting ◽  
Butyl Acetate ◽  
Reducing Power ◽  
Flow Cell ◽  
Acetoxy Group ◽  
Cyclic Ethers ◽  
Group Migration

E.p.r. spectra have been recorded for a number of radicals generated in a flow cell from cyclic ethers, 1,3-dioxolans, 1,3-dioxans, and other cyclic and acyclic substrates. The cyclic radicals do not undergo detectable fragmentation, but the rearrangement of the radical (9) derived from t-butyl acetate has been observed. The mechanism of acetoxy group migration in radicals is discussed in the light of these results. ��� The spectral data, including, in some cases, values of 13C hyperfine splitting factors, indicate that there is considerable deviation from planarity at the radical, centres of some cyclic species, and this phenomenon is accompanied by a change in sign of α-proton splitting factors. The reducing power of radicals derived from cyclic ethers has been investigated.

Facile synthesis of norbornene–ethylene–vinyl acetate/vinyl alcohol multiblock copolymers by the olefin cross-metathesis of polynorbornene with poly(5-acetoxy-1-octenylene)

2020 ◽  
Vol 11 (44) ◽  
pp. 7063-7077
Author(s):  
Yulia I. Denisova ◽  
Alexey V. Roenko ◽  
Olga A. Adzhieva ◽  
Maria L. Gringolts ◽  
Georgiy A. Shandryuk ◽  
...  
Keyword(s):  
Vinyl Acetate ◽  
Vinyl Alcohol ◽  
Ethylene Vinyl Acetate ◽  
Acetoxy Group ◽  
Multiblock Copolymers ◽  
Metathesis Reaction ◽  
Facile Synthesis ◽  
Cross Metathesis ◽  
Bond Hydrogenation

New norbornene−ethylene–vinyl acetate/vinyl alcohol multiblock copolymers are synthesized via the olefin cross-metathesis reaction of polynorbornene with poly(5-acetoxy-1-octenylene) followed by CC bond hydrogenation and acetoxy group deprotection.

Semimicro Determination of Sugar Configuration by Measurement of Circular Dichroism of Alditol Acetates

1973 ◽  
Vol 51 (2) ◽  
pp. 324-326 ◽  
Author(s):  
G. M. Bebault ◽  
J. M. Berry ◽  
Y. M. Choy ◽  
G. G. S. Dutton ◽  
N. Funnell ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Circular Dichroism ◽  
Structural Information ◽  
Acetoxy Group ◽  
Gas Liquid Chromatography ◽  
Circular Dichroïsm ◽  
Alditol Acetates

The configuration (D or L) of a sugar may be determined conveniently by circular dichroism measurements at 213 nm on alditol acetates, or their methylated derivatives, where the acetoxy group acts as a chromophore. Only milligram quantities of material are required and the method is well suited to analyzing fractions obtained by gas–liquid chromatography. Structural information which may be derived from the c.d. spectra is briefly discussed.

Instability of Some TWchothecenes in Methanol

1986 ◽  
Vol 69 (5) ◽  
pp. 902-903 ◽  
Author(s):  
Ru-Dong Wei ◽  
Fun S Chu
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Room Temperature ◽  
Early Stage ◽  
Acetoxy Group ◽  
Layer Chromatography

Abstract Stability of 8 trichothecenes stored in methanol at room temperature was studied by thin layer chromatography. Results indicate that the trichothecenes which bear an acetoxy group at both C3 and C4 are very susceptible to methanolysis. In the early stage, the acetoxy group at C3 is most favorable for the transesterification. All trichothecenes tested were transformed to several products after prolonged (22 days) exposure to methanol.

scholarly journals Enzymatic Deprotection of the Cephalosporin 3′-Acetoxy Group UsingCandida antarcticaLipase B

2010 ◽  
Vol 75 (4) ◽  
pp. 1289-1292 ◽  
Author(s):  
Leslie D. Patterson ◽  
Marvin J. Miller
Keyword(s):  
Acetoxy Group

scholarly journals (6-Acetoxy-2-acetylphenyl-κ2 C 1,O 1)tetracarbonylmanganese(I)

2007 ◽  
Vol 63 (11) ◽  
pp. m2655-m2655
Author(s):  
Victor D. Fester ◽  
Lyndsay Main ◽  
Brian K. Nicholson
Keyword(s):  
Title Compound ◽  
Intramolecular Interactions ◽  
Acetoxy Group

The title compound, [Mn(C10H9O3)(CO)4], is formed by orthomanganation of 3′-acetoxyacetophenone at the sterically crowded ortho site. The atoms of the benzene and the cyclometallated rings are coplanar to within <0.018 Å, and there are no significant intramolecular interactions between the Mn(CO)4 group and the adjacent acetoxy group.

scholarly journals (E)-2-[2-(3-Fluorophenyl)ethenyl]quinolin-8-yl acetate

2012 ◽  
Vol 68 (8) ◽  
pp. o2420-o2420
Author(s):  
Yan-Ping Huo ◽  
Xiao-Li Nie ◽  
Xiao-Ming Fang
Keyword(s):  
Hydrogen Bonds ◽  
Title Compound ◽  
Acetoxy Group ◽  
Dihedral Angles ◽  
Compound C

In the crystal of the title compound, C19H14FNO2, the molecules are linked by C—H...O hydrogen bonds in translational chains along thebaxis. The dihedral angles formed by the quinoline system with the fluorobenzene ring and the acetoxy group are 8.15 (3) and 77.42 (4)°, respectively.

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