Synthesis of anthracyclinones. Part 1. Regioselective alkylation of 5-hydroxyquinizarin

1984 ◽  
Vol 62 (10) ◽  
pp. 1922-1925 ◽  
Author(s):  
Laurence M. Harwood ◽  
Leslie C. Hodgkinson ◽  
James K. Sutherland ◽  
Patrick Towers
Keyword(s):  
Sodium Hydroxide ◽  
Alkyl Derivatives ◽  
Regioselective Alkylation ◽  
Hydroxide Water

Condensation of leuco-5-hydroxyquinizarin with aldehydes under Marschalk conditions (sodium hydroxide – water) gives 2-alkyl-5-hydroxyquinizarins with high regioselectivity, while the 3-alkyl compounds are obtained under Lewis conditions (piperidinium acetate – isopropanol). Reaction of the quinone with nitronate anions in methanol yields 2-alkyl derivatives exclusively.

The Cellulose — Sodium Hydroxide — Water System in the Cyanoethylation of Cotton Cellulose

1956 ◽  
Vol 26 (7) ◽  
pp. 518-523 ◽  
Author(s):  
J.W. Weaver ◽  
Elias Klein ◽  
Beverly G. Webre ◽  
Elsie F. DuPré
Keyword(s):  
Sodium Hydroxide ◽  
Water System ◽  
Cotton Cellulose ◽  
Hydroxide Water

Regioselective Alkylation of β-Cyclodextrin

1998 ◽  
Vol 51 (10) ◽  
pp. 915 ◽  
Author(s):  
Paramjit S. Bansal ◽  
Craig L. Francis ◽  
Noel K. Hart ◽  
Scott A. Henderson ◽  
David Oakenfull ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Dimethyl Sulfoxide ◽  
Sodium Hydroxide ◽  
Alkyl Halides ◽  
Barium Hydroxide ◽  
Analytical Methodology ◽  
Regioselective Alkylation ◽  
Benzyl Ethers ◽  
Hydroxy Groups

Methodology for preparation of heptakis(2,6-di-O-alkyl)-β-cyclodextrins, heptakis(2-O-alkyl)-β- cyclodextrins, and heptakis(6-O-alkyl)-β-cyclodextrins in substantially purified form has been developed. Treatment of β-cyclodextrin (1) with sodium or barium hydroxide and various alkyl halides in dimethyl sulfoxide or a mixture of dimethyl sulfoxide and N,N-dimethylformamide provided the corresponding heptakis(2,6-di-O-alkyl)-β-cyclodextrins. Treatment of heptakis(6-O-t-butyldimethylsilyl)-β-cyclodextrin (5) with sodium hydroxide and several haloalkanes in dimethyl sulfoxide followed by desilylation provided heptakis(2-O-alkyl)-β-cyclodextrins. Protection of the secondary hydroxy groups of the t-butyldimethylsilyl-β-cyclodextrin (5) as benzyl ethers, followed by desilylation, alkylation, and debenzylation afforded several heptakis(6-O-alkyl)-β-cyclodextrins. Analytical methodology has been developed to characterize all of these compounds, with the homogeneity of the pattern of substitution verified by h.p.l.c. analysis, f.a.b.–mass spectrometry and n.m.r. spectroscopy.

THE HEATS OF ADSORPTION AND WETTING OF MERCERIZED CELLULOSES BY SODIUM HYDROXIDE SOLUTIONS, WATER, AND METHYL ALCOHOL

1940 ◽  
Vol 18b (6) ◽  
pp. 168-179 ◽  
Author(s):  
J. L. Morrison ◽  
W. Boyd Campbell ◽  
O. Maass
Keyword(s):  
Crystal Lattice ◽  
Sodium Hydroxide ◽  
Methyl Alcohol ◽  
Internal Surface ◽  
Aqueous Sodium Hydroxide ◽  
Aqueous Sodium ◽  
Heats Of Adsorption ◽  
Heat Of Wetting ◽  
Irreversible Effects ◽  
Hydroxide Water

The heats of adsorption and wetting by aqueous sodium hydroxide, water, and methyl alcohol have been determined for celluloses mercerized at several different alkali concentrations. A quantity named the "heat of mercerization" has been determined, and it is considered to be a measure of the irreversible effects that distinguish mercerized from standard cotton cellulose, such as changed crystal lattice and enhanced internal surface. The extent of the latter change for the various mercerized celluloses has been shown by the heat of wetting measurements with water and methyl alcohol.

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