Acid-catalyzed addition of secondary amines to cyclopropyl ketones. Mass spectra of some cyclic aminobutyrophenones

1977 ◽  
Vol 42 (5) ◽  
pp. 850-855 ◽  
Author(s):  
Joseph Yovell ◽  
Daniel Hirsch ◽  
Shalom Sarel
Keyword(s):  
Mass Spectra ◽  
Secondary Amines ◽  
Acid Catalyzed ◽  
Cyclopropyl Ketones

Synthesis of 2-amino-5,7-dimethyl-4-oxopyrido[3,4-e]-1,3-thiazines

1983 ◽  
Vol 48 (12) ◽  
pp. 3426-3432 ◽  
Author(s):  
Dušan Koščík ◽  
Pavol Kristian ◽  
Ondrej Forgáč
Keyword(s):  
Spectral Data ◽  
Chlorine Atom ◽  
Mass Spectra ◽  
High Reactivity ◽  
Secondary Amines ◽  
Dimroth Rearrangement ◽  
H Nmr ◽  
New Synthesis ◽  
C Nmr

New synthesis of pyrido[3,4-e]-1,3-thiazines consisting in reaction of 2,6-dimethyl-4-chloronicotinoyl isothiocyanate with primary or secondary amines, or with benzaldehyde phenylhydrazone, is described. High reactivity of the chlorine atom does not allow isolation of the corresponding thioureas, arising as intermediates, except in the case of the benzylamino derivative. Structure of the products was unequivocally confirmed by their spectral data (IR, UV, 1H NMR, 13C NMR and mass spectra). The synthesized derivatives do not undergo the Dimroth rearrangement.

Cyclopropyl→cyclobutyl rearrangement in intramolecular cyclization of 3,5-bridged B-secoandrostane-6,7(or 5,7)-diols and mass spectra of products

1982 ◽  
Vol 47 (8) ◽  
pp. 2280-2290 ◽  
Author(s):  
Helena Velgová ◽  
Jorga Smolíková ◽  
Antonín Trka ◽  
Antonín Vítek
Keyword(s):  
Intramolecular Cyclization ◽  
Mass Spectra ◽  
Acid Catalyzed

Acid-catalyzed intramolecular cyclization of 6,7-dihydroxy-3α,5-cyclo-6,7-seco-5α-androstan-17-one (VII), 5,7-dihydroxy-3,5-methylene-5,7-secoandrostan-17-one and 5,7-dihydroxy-3β,5-cyclo-5,7-seco-A-homo-5β-androstan-17-one (XIII) in benzene and dioxane was investigated. The main cyclization products were 3,5-methylene-6-oxaandrostan-17-one (I) and/or 3β,5-cyclo-6-oxa-A-homo-5β-androstan-17-one (VIII). In the case of VI and VII the ratio of I and VIII was solvent-dependent: in benzene more VIII was formed than in dioxane. The mass spectra of I and VIII were almost identical and corresponded to the structure VIII.

Acid-catalyzed rearrangements of cyclopropyl ketones related to eudesmane

1980 ◽  
Vol 45 (19) ◽  
pp. 3798-3802 ◽  
Author(s):  
Drury Caine ◽  
Samuel Lindsay Graham ◽  
Tushar T. Vora
Keyword(s):  
Acid Catalyzed ◽  
Cyclopropyl Ketones

Synthesis and investigation of enamine-imine tautomerism of 2,6-disubstituted 4H-1,3-thiazin-4-ones

1982 ◽  
Vol 47 (12) ◽  
pp. 3268-3282 ◽  
Author(s):  
Ján Imrich ◽  
Pavol Kristian
Keyword(s):  
Aromatic Amines ◽  
Mass Spectra ◽  
Secondary Amines ◽  
Alkyl Aryl ◽  
Sodium Hydrosulfide ◽  
H Nmr ◽  
Electron Impact Mass ◽  
Aliphatic Thiols ◽  
Model Substances ◽  
Impact Mass

Substituted thioureas, obtained by reaction of 3-chloro-3-phenylpropenoyl isothiocyanate with primary aliphatic or aromatic amines, were cyclized to 2-N-alkyl(aryl)amino-6-phenyl-4H-1,3-thiazin-4-ones. The enamine-imine tautomerism was investigated by means of infrared and ultraviolet spectra and also by model substances prepared either by reacting the starting isothiocyanate with secondary amines, or by methylation of 2-N-alkyl(aryl)amino-6-phenyl-4H-1,3-thiazin-4-ones. The structure of the synthesized compounds was corroborated by 1H NMR and electron impact mass spectra. 2-N-Arylamino derivatives dissolved in chloroform exist prevalently an imino form whereas 2-N-alkylamino derivatives is an amino form. Reaction of 3-chloro-3-phenylpropenoyl isothiocyanate with aliphatic thiols gave 2-alkylthio-6-phenyl-4H-1,3-thiazin-4-ones and with sodium hydrosulfide (hydroselenide) 6-phenyl-2-thioxo-2,3-dihydro-4H-1,3-thiazin(selenazin)-4-ones.

Acid-catalyzed rearrangements of an A(1)-nor-triterpenoid 2α,3α-epoxide

1989 ◽  
Vol 54 (2) ◽  
pp. 413-429 ◽  
Author(s):  
Jiří Klinot ◽  
Jiří Liška ◽  
Alena Forgáčová ◽  
Miloš Buděšínský ◽  
Jiří Protiva ◽  
...  
Keyword(s):  
Acidic Medium ◽  
Boron Trifluoride ◽  
Mass Spectra ◽  
Boron Trifluoride Etherate ◽  
Methyl Group ◽  
Unsaturated Alcohols ◽  
Acid Catalyzed ◽  
C Nmr

Reactions of 2α,3α-epoxide X, derived from 19β,28-epoxy-A(1)-nor-18α-oleanane, with acids proceed with migration of the 10β-methyl group into the position 2β, giving rise to unsaturated alcohols XII and XIV and diene IX. Reaction with boron trifluoride etherate afforded ketone XI in addition to XII and XIV. Olefin VIII rearranged in acidic medium to give olefins XXVI and XXVII. The rearranged products were converted into other derivatives and their structure was established by 1H and 13C NMR, IR, UV and mass spectra.

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