Studies on intramolecular alkylation. XIV. The preparation of methoxylated cyclohexadienone derivatives from intramolecular diazoketone cyclizations inrelationship to isoquinoline alkaloid synthesis

1981 ◽  
Vol 34 (6) ◽  
pp. 1243 ◽  
Author(s):  
DW Johnson ◽  
LN Mander ◽  
TJ Masters
Keyword(s):  
Trifluoroacetic Acid ◽  
Isoquinoline Alkaloid ◽  
Intramolecular Alkylation ◽  
Alkaloid Synthesis ◽  
Tricyclic Compounds ◽  
Wide Range ◽  
Diazomethyl Ketones

A series of di- and tri-methoxytetrahydronaphthyl diazomethyl ketones (4), (6), (8), (25) and (27) have been prepared and cyclized in trifluoroacetic acid. A wide range of methoxylated cyclohexa- dienone containing tricyclic compounds (12), (15), (17), (18) and (30) were obtained as well as several rearranged derivatives, i.e. (13), (14), (32) and (33).

Studies on intramolecular alkylation. X. The acid-catalysed reactions of 5,8-Dialkoxy-1,2,3,4-tetrahydronaphthyl diazomethyl ketones

1978 ◽  
Vol 31 (7) ◽  
pp. 1561 ◽  
Author(s):  
DW Johnson ◽  
LN Mander
Keyword(s):  
Trifluoroacetic Acid ◽  
Acid Treatment ◽  
Polyphosphoric Acid ◽  
Intramolecular Alkylation ◽  
Naphthoic Acid ◽  
Acid Catalysed Reactions ◽  
Diazomethyl Ketones

5,8-Dimethoxy-3,4-dihydronaphthalen-1(2H)-one was converted into diazomethyl 5,8-dimethoxy-1,2,3,4-tetrahydro-2-naphthyl ketone (10) which, when treated with trifluoroacetic acid at 0°, gave 5,8- dimethoxy-4,4a-dihydro-3,4a-ethanonaphthalen-2(3H)-one (13), but at -15° gave 8-methoxy-1,2,3,4-tetrahydro-3,4a-ethanonaphthalene- 5(4aH),10-dione (14). 6-Methoxy-3,4-dihydronaphtha-len-1(2H)-one reacted with m-chloroperoxybenzoic acid to give 4,5-dihydro-1-benzoxepin-2(3H)-one (15) which after hydrolysis, ethylation and polyphosphoric acid treatment gave 5-ethoxy-8-methoxy-3,4-dihydronaphthalen-1(2H)-one (17). This compound was transformed into 5-ethoxy-8-hydroxy-1,2,3,4-tetrahydro-2-naphthoic acid (19) and thence to the ethoxy analogue of (14).

Studies on intramolecular alkylation. II. The preparation of intermediates for diterpene synthesis by intramolecular carbenoid addition reactions

1972 ◽  
Vol 25 (1) ◽  
pp. 137 ◽  
Author(s):  
DJ Beames ◽  
JA Halleday ◽  
LN Mander
Keyword(s):  
New Method ◽  
Addition Reactions ◽  
Dilute Acid ◽  
Ring Systems ◽  
Intramolecular Alkylation ◽  
Tricyclic Compounds ◽  
Cyclopropyl Ketones ◽  
Diazomethyl Ketones

A new method is described for the preparation of tricyclic compounds containing the 3,2,1- and 2,2,2-bicyclooctane ring systems. The copper-catalysed decomposition of the diazomethyl ketones derived from the olefinic acids (7), (9), (18), and (19) afforded, respectively, the cyclopropyl ketones (12), (13), (21), and (20). These compounds were transformed into the cyolopropyl diketones (15) and (22) which by treatment with dilute acid or base gave, in turn, the bridged octalones (1) and (2).

Regioselectivity in isoquinoline alkaloid synthesis

2010 ◽  
Vol 51 (13) ◽  
pp. 1774-1778 ◽  
Author(s):  
Rodolfo Quevedo ◽  
Edwin Baquero ◽  
Mario Rodriguez
Keyword(s):  
Isoquinoline Alkaloid ◽  
Alkaloid Synthesis

scholarly journals The chemical composition of polyphenolic compounds Achillea micranthoides Klok. herbs

2020 ◽  
pp. 80-87
Author(s):  
I. F. Duyun ◽  
O. V. Mazulin ◽  
G. V. Мazulin ◽  
Т. V. Oproshanska
Keyword(s):  
Trifluoroacetic Acid ◽  
Practical Interest ◽  
Polyphenolic Compounds ◽  
Hydroxycinnamic Acids ◽  
Biologically Active ◽  
Herbal Remedies ◽  
Actual Problem ◽  
Mediterranean Countries ◽  
Wide Range ◽  
Anti Inflammatory

For obtain modern herbal remedies, medicinal plants containing flavonoids and hydroxycinnamic acids are promising. These polyphenolic compounds are characterized by structural diversity, non-toxicity, a wide range of pharmacological activity. An actual problem is the development of new modern instrumental research methods. In scientific and folk medicine the genus Achillea L. of the Asteraceae L. family are widely used to accelerate wound healing, stop bleeding of various etiologies, as anti-inflammatory and anthelmintic agents. The herb of Achillea micranthoides Klok. has theoretical and practical interest. The plant is distributed in the southern regions of the Black Sea and Mediterranean countries, Europe, Ukraine. A long growing season contributes to the accumulation of biologically active polyphenolic compounds from groups of flavonoids and hydroxycinnamic acids. The aim of the work was to study the composition of polyphenolic compounds (flavonoids and the hydroxycinnamic acids) in the herbs of the Achillea micranthoides Klok. during flowering (june-september). The object of research was herb of Achillea micranthoides Klok. Harvesting was carried out in south and oust regions of Ukraine during flowering (June–September, 2017). The investigation of polyphenolic compounds were performed by TLC and HPLC methods. HPLC analyzes were performed using an Agilent Technogies (Model 1100) (Japan). The chromatographic column ZORBAX-SB C-18 measuring 2.1×150 mm, filled with octadecylsilyl sorbent, with a grain diameter of 3.5 microns were used. The systems as the mobile phase: trifluoroacetic acid 0,2%, methanol anhydrous and a mixture of trifluoroacetic acid 0,2% with methanol 70% were used; wave length 313 nm, 350 nm.             During the flowering period, the presence and quantitative content were established 8 flavonoids (up to 1,176 ± 0,122%) and 6 hydroxycinnamic acids (up to 0,807 ± 0,071%). The identified flavonoids are dominated by compounds: apigenin-7,4'-di-O-glucoside, quercetin-3-O-rutinoside, luteolin-6-C-glucoside, luteolin-7-O-β-D-glucopyranoside, apigenin-7-O-β-D-glucopyranoside. The highest content in the composition of hydroxycinnamic acids was found for chlorogenic and caffeic acids. The obtained results to be used for perspective modern herbal remedies from Achillea micranthoides Klok. herb with anti-inflammatory, antioxidative, haemostatic and hepatoprotective activities. The qualitative and quantitative determination methods of polyphenolic compounds in Achillea micranthoides Klok. herb may be used to the State Ukraine Pharmacopoeia monographs.

Studies on intramolecular alkylation. III. The preparation of γ-lactams from podocarpic acid: Models for diterpene alkaloid synthesis

1974 ◽  
Vol 27 (6) ◽  
pp. 1245 ◽  
Author(s):  
BS Balgir ◽  
LN Mander ◽  
RH Prager
Keyword(s):  
Diterpene Alkaloid ◽  
Intramolecular Alkylation ◽  
Alkaloid Synthesis

Several methods for the introduction of a 6β,16 nitrogen bridge in podocarpane derivatives are described. Attempted intramolecular N-alkylation in the 6α-bromo amide (9) gave ketol (13) via imino ether (10). Attempted lactam formation from the 6-oxo nitrile (22) or 6-oxo ester (24) gave no useful result, but the diosphenol(15) gave lactam (16), which was reduced to the target lactam (28). A further route to (28) via the 6-ene derivative of amide (7) is also described. The lack of identity between (28) and the γ-lactam formed from photolysis of O-methylpodocarpoyl azide indicated that this lactam has the 2β,19 structure (31).

Studies on intramolecular alkylation. V. Intramolecular alkylation of the aromatic ring in tetrahydronaphthyl diazomethyl ketones

1974 ◽  
Vol 27 (6) ◽  
pp. 1269 ◽  
Author(s):  
DJ Beames ◽  
TR Klose ◽  
LN Mander
Keyword(s):  
Aromatic Ring ◽  
Methyl Ether ◽  
Intramolecular Alkylation ◽  
Acid Catalysed Reactions ◽  
Diazomethyl Ketones

The acid-catalysed reactions in weakly nucleophilic environments of 2-diazoacetyl-l,2,3,4-tetrahydronaphthalene (ll), of 6-diazoacetyl-5,6,7,8-tetrahydro-2-naphthol (2), of 6-diazoacetyl-5,6,7,8- tetrahydro-2-naphthyl methyl ether (3) and its 2,8 and 2,5 isomers (14) and (17), and of 6-diazo- acetyl-5,6,7,8-tetrahydro-6-trifluoroacetoxy-2-naphthyl methyl ether (9) have been studied. Several of the spirocyclohexa-2,5-dienone derivatives prepared thus, (4), (8) and (16), provide potential intermediates or models for the synthesis of tetracyclic diterpenoids.

scholarly journals Influence of atmospheric conditions on the role of trifluoroacetic acid in atmospheric sulfuric acid–dimethylamine nucleation

2021 ◽  
Vol 21 (8) ◽  
pp. 6221-6230
Author(s):  
Ling Liu ◽  
Fangqun Yu ◽  
Kaipeng Tu ◽  
Zhi Yang ◽  
Xiuhui Zhang
Keyword(s):  
Sulfuric Acid ◽  
Trifluoroacetic Acid ◽  
Density Functional ◽  
Cluster Formation ◽  
Formation Rate ◽  
Urban Environments ◽  
Nucleation Process ◽  
Atmospheric Conditions ◽  
Wide Range

Abstract. Ambient measurements combined with theoretical simulations have shown evidence that the tropospheric degradation end-products of Freon alternatives, trifluoroacetic acid (TFA), one of the most important and abundant atmospheric organic substances, can enhance the nucleation process based on sulfuric acid (SA) and dimethylamine (DMA) in urban environments. However, TFA is widespread all over the world under different atmospheric conditions, such as temperature and nucleation precursor concentration, which are the most important factors potentially influencing the atmospheric nucleation process and thus inducing different nucleation mechanisms. Herein, using the density functional theory combined with the Atmospheric Cluster Dynamics Code, the influence of temperature and nucleation precursor concentrations on the role of TFA in the SA–DMA nucleation has been investigated. The results indicate that the growth trends of clusters involving TFA can increase with the decrease in temperature. The enhancement on particle formation rate by TFA and the contributions of the SA–DMA–TFA cluster to the cluster formation pathways can be up to 227-fold and 95 %, respectively, at relatively low temperature, low SA concentration, high TFA concentration, and high DMA concentration, such as in winter, at the relatively high atmospheric boundary layer, or in megacities far away from industrial sources of sulfur-containing pollutants. These results provide the perspective of the realistic role of TFA in different atmospheric environments, revealing the potential influence of the tropospheric degradation of Freon alternatives under a wide range of atmospheric conditions.

A Study of Optimum Conditions for Electrospinning Cellulose Acetate Nanofibers in Trifluoroacetic Acid Solvent

2013 ◽  
Vol 750-752 ◽  
pp. 323-327
Author(s):  
Edison Omollo ◽  
Chu Yang Zhang ◽  
Wan Jun Liu ◽  
Ncube Sizo
Keyword(s):  
Cellulose Acetate ◽  
Flow Rate ◽  
Trifluoroacetic Acid ◽  
Low Flow ◽  
Optimum Conditions ◽  
Flow Rates ◽  
Medium Voltage ◽  
Wide Range ◽  
Viscous Solution

Cellulose acetate (CA) nanofibers were electrospun in trifluoroacetic acid (TFA) under various conditions of concentration, voltage and dope flow rate while tip to collector distance (TCD) kept constant. Results showed that concentrations lower than 8 wt. % could only be electrospun at low flow rates. Bead free fibers were easily electrospun from higher CA concentrations 13 wt. % to 15 wt. %. Concentrations greater than 15 wt. % formed a viscous solution that could not be uniformly dispersed, thus impeding electrospinning. Medium voltage 20KV was found to produce good fibers while flow rates of 0.5ml/h and above, produced non-uniform fibers with a wide range. Average fiber diameters of 104nm and 129nm were formed at 13 wt. % and 15 wt. % (0.4ml/h, 20KV) respectively.

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