scholarly journals The Spatial Configurations and the Ultraviolet Absorption Spectra of Biphenyl and Some Related Compounds

1954 ◽  
Vol 27 (9) ◽  
pp. 597-601 ◽  
Author(s):  
Hiroshi Suzuki
Keyword(s):  
Absorption Spectra ◽  
Ultraviolet Absorption ◽  
Spatial Configurations ◽  
Related Compounds

Colouring Matters of Australian Plants. II. Naphthoquinones from Diospyros hebecarpa A. Cunn

1952 ◽  
Vol 5 (4) ◽  
pp. 760 ◽  
Author(s):  
RG Cooke ◽  
H Dowd
Keyword(s):  
Absorption Spectra ◽  
Ultraviolet Absorption ◽  
Ether Extraction ◽  
New Compounds ◽  
Related Compounds

Ether extraction of Diospyros hebecarpa A. Cunn. yields plumbagin, and two new compounds which are shown to be 5-hydroxy-7-methyl-1,4-naphthoquinone and 1,4-diketo-5-hydroxy-7-methyl-1,2,3,4-tetrahydronaphthalene. The ultraviolet absorption spectra of these and related compounds are recorded, and the synthesis of 1,4,5-tri-methoxy-7-methylnaphthalene is described.

TRYPTAMINES, CARBOLINES, AND RELATED COMPOUNDS: PART IX. THE CYCLIZATION OF SOME NITRO- AND AZIDO-PHENYLPYRIDINES. PYRIDO[1,2-b]INDAZOLE

1961 ◽  
Vol 39 (12) ◽  
pp. 2516-2528 ◽  
Author(s):  
R. A. Abramovitch ◽  
K. A. H. Adams
Keyword(s):  
Absorption Spectra ◽  
Catalytic Reduction ◽  
Nitro Compounds ◽  
Ultraviolet Absorption ◽  
The Other ◽  
Azo Compounds ◽  
Minute Amount ◽  
Ferrous Oxalate ◽  
Related Compounds ◽  
General Method

Heating 2-o-nitrophenylpyridine with ferrous oxalate gives rise to pyrido[1,2-b]indazole (III). The evidence for the structure of this compound is discussed. Similarly, heating 2-o-nitrophenylpyridine methiodide and N-oxide with ferrous oxalate gives (III), in each case, demethylation and deoxygenation preceding the cyclization. In the latter case a minute amount of δ-carboline is also formed. Heating pyridine-N-oxides with ferrous oxalate is a potentially general method of effecting deoxygenations of these compounds. Contrary to the results of Smith and Boyer (11), it is found that heating 2-o-azidophenylpyridine also gives rise to (III). On the other hand, the action of heat on 2-o-azidophenyIpyridine-N-oxide gives a mixture of δ-carboline and δ-carboline-py-N-oxide in low yield. The mechanism of the cyclization of the azides and of the reaction taking place on heating nitro-compounds with ferrous oxalate is discussed briefly; the formation of a nitrene intermediate is favored.The catalytic reduction of 2-o-nitrophenylpyridine-N-oxide giving rise to the azoxy-, azo-, and hydrazo-derivatives is described and the ultraviolet absorption spectra of these compounds are discussed. It is concluded the steric inhibition of coplanarity exists in the azoxy- and azo-compounds leading to the lack of effective conjugation across the N=N bond.

Sign in / Sign up

Export Citation Format

Share Document