The thermaldecomposition of spiro-1-pyrazolines 2 obtained by the cycloaddition of exocyclic α,β-unsaturated ketones with diazomethane gives spirocyclopropanes 4 with high selectivity and the new β-methyl-3-benzylidene derivatives 3. The configuration and conformation of the thermolysis products 3 and 4 were elucidated by different n.m.r. methods.
Reaction of substituted spiro[1,2,3,4-tetrahydronaphthalene-2,3′-(1′-pyrazolines)] with chlorinating reagents
作者:A. P. Molchanov、V. S. Korotkov、R. R. Kostikov
DOI:10.1134/s1070428006080070
日期:2006.8
In reaction of 4'-arylspiro[1,2,3,4-tetrahydronaphthalene-2,3'-(1'-pyrazolin)]-1-ones with N-chloro-succinimide formed spirocyclic substituted 3-chloro-1-pyrazolines that lost nitrogen at heating transforming into spirocyclic chlorocyclopropanes. The reaction of the same pyrazolines with chlorine led to the formation of spirocyclic gem-dichlorocyclopropanes.
Reactions of Aliphatic Diazo Compounds: VI. Reactions of Diazomethane and Ethyl Diazoacetate with (E)-2-Arylmethylene-1,2,3,4-tetrahydronaphthalen-1-ones
作者:A. P. Molchanov、V. S. Korotkov、R. R. Kostikov
DOI:10.1023/b:rujo.0000036064.74236.19
日期:2004.4
Diazomethane and ethyl diazoacetate add to (E)-2-arylmethylene-1,2,3,4-tetrahydronaphthaten-1-ones in a regio- and stereoselective fashion, yielding the corresponding 4'-aryl-1,2,3,4,4',5'-hexahydro-3'H-naphthalene-2-spiro-3'-pyrazol-1-ones. The products formed by addition of ethyl diazoacetate undergo isomerization into 4,5-dihydro-1H-pyrazole derivatives.
Synthesis, tautomerism and stereochemistry of spiropyrazolines
作者:Gábor Tóth、Albert Lévai、Helmut Duddeck
DOI:10.1002/mrc.1260300308
日期:1992.3
cis‐spiro‐1‐pyrazolines, respectively, regio‐ and stereo‐selectively in a one‐step reaction. These rearrange into spiro‐2‐pyrazolines on proton catalysis. The relative configurations and conformations of the spiropyrazolines were elucidated by different NMR methods.