scholarly journals SYNTHESIS AND REACTIONS OF 1-(4’-BROMOPHENACYL)-3-(4’-BROMO-PHENYL)-4,6-DIMETHOXYINDOLE

2010 ◽  
Vol 5 (2) ◽  
pp. 156-162
Author(s):  
Jumina Jumina
Keyword(s):  
Acetic Acid ◽  
Sodium Borohydride ◽  
Trifluoroacetic Acid ◽  
Boron Trifluoride ◽  
Polyphosphoric Acid ◽  
Glacial Acetic Acid ◽  
Boron Trifluoride Etherate ◽  
Phosphoryl Chloride ◽  
Acetyl Ester ◽  
Toluenesulfonic Acid

  1-Phenacyl-3-aryl-4,6-dimethoxyindoles 2b and 2c were obtained in good yields respectively through cyclization of N,N-diphenacylaniline 1b and 1c in trifluoroacetic acid. However, instead of giving pyrroloindole 3c, treatment of phenacylindole 2c with polyphosphoric acid afforded indolizine 5 in 42% yield. Phenacylindole 2c reacts with the Vilsmeier aroylation reagent consisted of a mixture of phosphoryl chloride and p-chloro-N,N-dimethylbenzamide to give 2-aroylindole 6 (32%) and pyrroloindole 7 (22%). When treated with sodium borohydride, phenacylindole 2c gave alcohol 8 in 83% yield. Nonetheless, treatment of alcohol 8 with either p-toluenesulfonic acid in glacial acetic acid or boron trifluoride etherate in benzene did not give the desired dihydropyrroloindole 12. Instead, the reactions afforded respectively acetyl ester 9 and indole 10 in 56% and 63% yield.   Keywords: phenacylindole, aroylindole, pyrroloindole, and indolizine.

Ipso nitration. XVIII. Nitrationof 2-chloro-1,3,5-trimethylbenzene: nitration ipso to chlorine

1978 ◽  
Vol 56 (10) ◽  
pp. 1348-1357 ◽  
Author(s):  
Alfred Fischer ◽  
Sachdev Singh Seyan
Keyword(s):  
Acetic Acid ◽  
Ambient Temperature ◽  
Trifluoroacetic Acid ◽  
Boron Trifluoride ◽  
Boron Trifluoride Etherate ◽  
Trifluoroacetic Anhydride ◽  
Trans Isomers ◽  
Dimethyl Benzyl ◽  
Cis And Trans Isomers ◽  
Cis And Trans

Nitration of 2-chloro-1,3,5-trimethylbenzene in acetic anhydride gives the cis and trans isomers of 4-chloro-1,3,5-trimethyl-4-nitrocyclohexa-2,5-dienyl acetate (1, 21%), the cis and trans isomers of 3-chloro-2,4,6-trimethyl-4-nitrocyclohexa-2,5-dienyl acetate (2, 6%), and 2-chloro-1,3,5-trimethyl-4-nitrobenzene (73%). Diene 1 reacts with acidified aqueous acetone to form the corresponding dienol, acidified methanol to form the methyl ether, and hydrogen chloride to form the corresponding chloride. In acetic acid a mixture of 4-chloro-3,5-dimethyl-benzyl derivatives and 3-chloro-2,4,6-trimethylphenyl acetate are formed. In trifluoroacetic acid – trifluoroacetic anhydride and also in boron trifluoride etherate, 2-chloro-1,3,5-trimethyl-4-nitrobenzene is the predominant product. Diene 2 on reaction with acetic acid, acidified methanol, trifluoroacetic acid – trifluoroacetic anhydride, and boron trifluoride etherate gives 3-chloro-2,4,6-trimethylphenyl acetate. Some 2-chloro-4-nitromesitylene is obtained in trifluoromethanesulfonic acid. Diene 2 also gives the acetate on standing at ambient temperature or at −20 °C, and on pyrolysis. Diene 1 gives 4-chloro-3,5-dimethylphenylnitromethane on standing at ambient temperature or at −20 °C but a mixture of 2-chloro-1,3,5-trimethyl-4-nitrobenzene, chloromesitylene, and 3-chloro-2,4,6-trimethylphenyl acetate on pyrolysis.

Synthesis and structure of a stegane from dimethylmatairesinol

1984 ◽  
Vol 37 (8) ◽  
pp. 1775 ◽  
Author(s):  
RC Cambie ◽  
GR Clark ◽  
PA Craw ◽  
PS Rutledge ◽  
PD Woodgate
Keyword(s):  
Trifluoroacetic Acid ◽  
Oxidative Coupling ◽  
Boron Trifluoride ◽  
Boron Trifluoride Etherate ◽  
High Yield ◽  
X Ray Diffraction ◽  
X Ray

Oxidative coupling of dimethylmatairesinol with thallium tristrifluoroacetate (prepared in situ from thallium(III) oxide and trifluoroacetic acid) and boron trifluoride etherate gives a high yield of an isostegane which has been isomerized thermally to a stegane. Stereochemical assignments have been confirmed by X-ray diffraction studies.

6H-Dibenzo[b,d]pyrans. I. Synthesis

1975 ◽  
Vol 53 (3) ◽  
pp. 343-349 ◽  
Author(s):  
John P. Devlin
Keyword(s):  
Carboxylic Acid ◽  
Sodium Borohydride ◽  
Boron Trifluoride ◽  
Boron Trifluoride Etherate ◽  
Ring Cleavage ◽  
Borohydride Reduction ◽  
Grignard Addition ◽  
Sodium Borohydride Reduction

The preparation of 2′,4′-dihydroxy- and 2′,6′-dihydroxybiphenyl-2-carboxylic acid lactones (3 and 4) is described. Grignard addition to or direct boron trifluoride etherate – sodium borohydride reduction of these lactones yields respectively these 6,6-substituted (e.g. 6) or the 6,6-unsubstituted (13a) 6H-dibenzo[b,d]pyrans. Evidence that the reductive route proceeds without ring cleavage is presented.

New heterocycles derived from 2-aminothiophenol

1971 ◽  
Vol 24 (2) ◽  
pp. 405 ◽  
Author(s):  
JL Huppatz ◽  
RMJ Moore
Keyword(s):  
Dicarboxylic Acid ◽  
Spectral Data ◽  
Sulphuric Acid ◽  
Propionic Acid ◽  
Sodium Borohydride ◽  
Polyphosphoric Acid ◽  
Heterocyclic Ring ◽  
Phosphoryl Chloride ◽  
Alternative Synthesis ◽  
Derivatives Of

2-Aminothiophenol reacted with β-propiolactone in ethanol to give β-[o- (β-carboxyethylamino)phenylthio]propionic acid (1) which underwent cyclodehydration in polyphosphoric acid to give derivatives of two new heterocyclic ring systems, viz., 1,8-dioxo-1,2,3,4,5,6,7,8-octahydro-4- thia-5-azaphenanthrene (2) and 4,8-dioxo-3,4,7,8-tetrahydro-2H,6H- [1,4]thiazepino[2,3,4-ij]quinoline (3). Analytical and spectral data are presented which support the structures proposed for these compounds. ��� Alternative synthesis of each heterocycle was achieved by using media other than polyphosphoric acid to cyclize the dicarboxylic acid (1). Phosphoryl chloride gave β-(4-oxo-2,3,4,5-tetrahydro-1,5- benzothiazepin-5-yl)propionic acid (4), which was cylodehydrated smoothly to the thiazepine (3). Concentrated sulphuric acid afforded β- (4-oxo-1,2,3,4-tetrahydroquinol-8-ylthio)propionic acid (6) which was converted into the thiazaphenanthrene (2) by polyphosphoric acid. ��� Bromination reactions and reduction with sodium borohydride of the thiazepine (3) are also described.

Synthetic Studies of anti-Leukaemic Alkaloids, IX* / Some Aspects of the Chemistry of C atliar anthine

1978 ◽  
Vol 33 (4) ◽  
pp. 469-470 ◽  
Author(s):  
Atta-ur -Rahman ◽  
Sadiqa Firdous ◽  
Anwer Basha
Keyword(s):  
Acetic Acid ◽  
Sodium Borohydride ◽  
Glacial Acetic Acid ◽  
Indole Alkaloids ◽  
Life Time ◽  
Chemotherapeutic Agents ◽  
Vinca Rosea ◽  
French Group ◽  
One Step ◽  
Indoline Alkaloids

Abstract Vinblastine and Vincristine are binary indole-indoline alkaloids occurring in traces in the leaves of Vinca rosea. They are among the most powerful chemotherapeutic agents available to man for the treatment of a variety of cancers. Their high cost and complexity of structure has attracted the attention of many eminent chemists towards their synthesis. The first synthesis of both these anti-tumour alkaloids was reported by us last year [7] starting from two major alkaloids, catharanthine and vindo-line, which co-occur in the same plant. Some aspects of the chemistry of catharanthine are now presented including a novel one-step de-carbomethoxylation reaction with H2S in glacial acetic acid and a reversible isomerization of catharanthine with sodium borohydride. A study of the life-time of catharanthine in hot glacial acetic acid substantiates the earlier work of the Anglo-French group on the biosynthesis of indole alkaloids.

Some acid-catalysed reactions of indol-3-yl and indol-2-yl disubstituted methanols

2009 ◽  
Vol 74 (7-8) ◽  
pp. 1137-1150 ◽  
Author(s):  
Mardi Santoso ◽  
Naresh Kumar ◽  
David StClair Black
Keyword(s):  
Crystal Structure ◽  
Boron Trifluoride ◽  
Boron Trifluoride Etherate ◽  
X Ray ◽  
Toluenesulfonic Acid ◽  
Acid Catalysed Reactions

1-Substituted indol-3-yl and indol-2-yl disubstituted methanols do not undergo acid-catalysed trimerisation to yield indolocyclotriveratrylenes, unlike the related primary 1-substituted indol-3-yl- and -2-ylmethanols. The 1-substituted indol-3-ylmethanols 10 and 11 gave diindol-3-ylmethanes 12 and 13, respectively, on treatment with p-toluenesulfonic acid in dichloromethane. In contrast, the indol-2-ylmethanols 22 and 23 gave the reduced indolo[3,2-b]carbazoles 24 and 25, respectively, on treatment with boron trifluoride etherate in benzene. An X-ray crystal structure of compound 24 is described.

Experiments Directed Towards the Synthesis of Anthracyclinones. XXIX. Fluoro-Substituted Tetracycles

1996 ◽  
Vol 49 (7) ◽  
pp. 751 ◽  
Author(s):  
RC Cambie ◽  
KC Higgs ◽  
JJ Rustenhoven ◽  
PS Rutledge
Keyword(s):  
Acetic Acid ◽  
Boron Trifluoride ◽  
Reaction Times ◽  
Chair Conformation ◽  
Boron Trifluoride Etherate ◽  
Side Chain ◽  
Equatorial Position ◽  
Acid Complex ◽  
Slow Reaction

Diastereoselective formation of 9-fluoro-9-methylanthracyclinones has been achieved by treating ortho-methallyl-substituted anthraquinonyl homochiral dioxans with boron trifluoride etherate . The demethoxy anthraquinonyl dioxan (16) underwent slow reaction to give exclusively the (7S,9R) fluoro tetracycle (21) in 58% yield. The dimethoxy anthraquinonyl dioxan (15) was less reactive, allowing other reactions to compete, but boron trifluoride -acetic acid complex effected rapid cyclization of (15) with high diastereoselectivity. Short reaction times with this reagent circumvented the formation of the alkenes (25) and the naphthacenedione (9). Boron trifluoride-nitromethane gave the (7S,9R) fluoro tetracycle (19) in 36% yield. Although the yields of the fluoro tetracycles were modest, they compare favourably with a 4% yield reported for the fluorination of daunomycinone. The 6-demethoxy tetracycle (21) has been shown to exist in the expected half-chair conformation, with the bulky C7 side chain in a pseudo-equatorial position. In contrast, the 6,11-dimethoxy fluoro tetracycle (19) exists in a significantly perturbed half-chair conformation with a pseudo-axial side chain.

Collaborative Study of a Method for the Identification of Afiatoxin B1 by Derivative Formation

1967 ◽  
Vol 50 (2) ◽  
pp. 354-360 ◽  
Author(s):  
Leonard Stoloff
Keyword(s):  
Acetic Acid ◽  
Formic Acid ◽  
Silica Gel ◽  
Thionyl Chloride ◽  
Trifluoroacetic Acid ◽  
Glacial Acetic Acid ◽  
Collaborative Study ◽  
Side Reaction ◽  
Chromatographic Behavior ◽  
Definition Of

Abstract A modification of the Andrellos procedure for identification of afiatoxin B1 was studied collaboratively in 19 laboratories. The procedure, based on the altered chromatographic behavior of the afiatoxin after reactions with trifluoroacetic acid, formic acid/thionyl chloride, and glacial acetic acid/thionyl chloride, was modified by an improved silica gel column cleanup and a clearer definition of sources of difficulty. Each collaborator examined 3 extract samples: two naturally contaminated with 5 μg afiatoxin B1/sample, and one aflatoxin-free extract to which an afiatoxin B2 artifact was added. No false identifications were made. Sixteen laboratories obtained reasonably good results with the trifluoroacetic acid and formic acid/thionyl chloride reagents. Twelve laboratories obtained reasonably good results with the acetic acid/thionyl chloride reagent but there was general difficulty with a side reaction assumed to be caused by inability to maintain anhydrous conditions. The method was recommended for adoption as official, first action.

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