Compounds derived from hydroxyacetic acids
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Chapter 6. Compounds derived from hydroxyacetic acids 1-(3,5-Dichloro-2-hydroxyphenyl)-2-hydroxyethanone [58483-53-7]
C8H6Cl2O3 Synthesis
OH COCH 2OH
Cl
mol.wt. 221.04
-Refer to: [268] (Romanian patent).
Cl 1-(5-Chloro-2-hydroxyphenyl)-2-hydroxyethanone [52728-05-9]
C8H7ClO3
mol.wt. 186.59
Synthesis
OH COCH 2OH
Cl
-Obtained by oxidative rearrangement of 5-chloro-2-hydroxyα-bromoacetophenone in moist DMSO for 16 h at 20° (56%) [416]. m.p. 98-99° [416];
1H
NMR [416].
1-(3,4-Dihydroxy-5-nitrophenyl)-2-hydroxyethanone [134612-56-9]
C8H7NO6 Synthesis
OH NO2
mol.wt. 213.15
OH
-Refer to: [163].
COCH 2 OH 2-Hydroxy-1-(2-hydroxyphenyl)ethanone [17375-96-1]
C 8H 8O 3
mol.wt. 152.15
Syntheses
OH
-Preparation by treatment of 2-hydroxy-α-bromoacetophenone with refluxing water for 16 h (88%) [145]. -Also obtained by hydrolysis of 2-hydroxy-α-(benzoyloxy)acetophenone with 50% aqueous potassium hydroxide in refluxing ethanol for 34 h (73%) [416]. -Also obtained by oxidative rearrangement of 2-hydroxy-α-bromoacetophenone in moist DMSO for 16 h at 20° (31%) [416]. -Also obtained by action of hot aqueous sodium carbonate on 2,3-dihydro-2-hydroxybenzo[b] furan-3-one (m.p. 108°) (SM) at 100° for 1 h (33%). SM was obtained by oxidation of 2-hydroxyacetophenone with selenium dioxide [658]. -Also obtained by hypervalent iodine oxidation of 1-(trimethylsilyloxy)-1-[2-(trimethylsilyloxy)phenyl]ethene with iodosobenzene, boron trifluoride etherate and water. The mixture was stirred COCH 2OH
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HYDROXYACETOPHENONES
at -40° for 1 h, then the temperature was slowly (1 h) raised to r.t. and stirring was continued for 30 min (25%) [1033]. -Also obtained by a selective one-step synthesis from phenoxymagnesium bromide (1 mol) and anhydrous monomeric glyoxal (1 mol) in boiling benzene for 20 h (24%) [271]. -Also obtained from α-chloro-o-hydroxyacetophenone by hydrolysis with boiling water for 15-20 h (20%) [1524]. -Also refer to: [23] [24] [341] [390] [524] [823] [847]. m.p. 66-67° [658], 65° [271] [1524], 64-65° [145] [416] [1033]; NMR [271] [416] [658], IR [271], UV [271].
1H
2-Hydroxy-1-(3-hydroxyphenyl)ethanone [131341-58-7]
C8H 8O 3
mol.wt. 152.15
Synthesis
OH
-Refer to: [607]. COCH2OH 2-Hydroxy-1-(4-hydroxyphenyl)ethanone [5706-85-4]
C 8H 8O 3 OH
mol.wt. 152.15
Syntheses
-Preparation by reaction of p-hydroxy-α-bromoacetophenone with formic acid in the presence of DBU, *in benzene at 0°, followed by saponification of the intermediate formate ester with sodium hydroxide in COCH2OH methanol (99%) [1139]; *in methylene chloride, with the same treatment (49%) [560]. -Preparation by demethylation of α-acetoxy-p-methoxyacetophenone (SM) with aluminium chloride in refluxing benzene for 3 h (80%). In the reaction, deacetylation takes place simultaneously. SM was obtained by treatment of α-chloro-p-methoxyacetophenone with potassium acetate in ethanol [279]. -Preparation by action of boron trifluoride etherate with p-hydroxyphenyl diazomethyl ketone (SM1) in nitromethane under nitrogen at 22° for 15 min (81
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