Nucleophilic cleavage of the germanium–oxygen bond: acid-catalysed hydrolysis of phenoxygermanes

1974 ◽  
pp. 1331-1333 ◽  
Author(s):  
John R. Chipperfield ◽  
Geoffrey E. Gould
Keyword(s):  
Nucleophilic Cleavage ◽  
Hydrolysis Of ◽  
Oxygen Bond

Reactions of acyl phosphates. Base hydrolysis of [Co(NH3)5OPO3COCH3]+ and the metal hydroxide promoted hydrolysis of acetyl phenyl phosphate

1981 ◽  
Vol 34 (8) ◽  
pp. 1769 ◽  
Author(s):  
DA Buckingham ◽  
CR Clark
Keyword(s):  
Hydroxo Complex ◽  
Metal Hydroxide ◽  
Base Hydrolysis ◽  
Acetyl Phosphate ◽  
Carbonyl Carbon ◽  
Phenyl Phosphate ◽  
Hydrolysis Of ◽  
Oxygen Bond

Tracer 18O studies have established that base hydrolysis of coordinated acetyl phosphate in [(NH3)5Co-OPO3COCH3]+ (kOH 0.53 mol-1 dm3 s-1, 25°C, I 1.0 NaClO4) proceeds with exclusive carbon-oxygen bond fission. The hydrolysis of acetyl phenyl phosphate monoanion is significantly catalysed by the exchange-inert hydroxo complex [(NH3)5Co-OH]2+ (kMOH 2.9 × 10-2 mol-1 dm3 s-1, 25°) which operates through a nucleophilic pathway involving attack at carbonyl carbon.

Kinetics of the hydrolysis of acyl chlorides in pure water

1967 ◽  
Vol 45 (14) ◽  
pp. 1619-1629 ◽  
Author(s):  
A. Queen
Keyword(s):  
Pure Water ◽  
Activation Parameters ◽  
Acyl Chlorides ◽  
Reversible Addition ◽  
Electron Donation ◽  
Kinetics Of ◽  
Hydrolysis Of ◽  
Chlorine Bond ◽  
Oxygen Bond ◽  
Bimolecular Mechanism

The activation parameters ΔH≠, ΔS≠, and ΔCP≠ for the hydrolyses of a series of alkyl chloroformates and dimethylcarbamyl chloride in water have been determined. The results indicate that, with increasing electron donation to the chlorocarbonyl group, the mechanism changes from bimolecular to unimolecular (SN1) displacement at this position. For isopropyl chloroformate, some concurrent alkyl–oxygen bond fission is also indicated. The bimolecular mechanism involves reversible addition of water to the carbonyl group followed by ionization of the carbon–chlorine bond.

scholarly journals A novel mechanism of enzymic ester hydrolysis. Inversion of configuration and carbon-oxygen bond cleavage by secondary alkylsulphohydrolases from detergent-degrading micro-organisms

1977 ◽  
Vol 165 (3) ◽  
pp. 575-580 ◽  
Author(s):  
B Bartholomew ◽  
K S Dodgson ◽  
G W J Matcham ◽  
D J Shaw ◽  
G F White
Keyword(s):  
Bond Cleavage ◽  
Hydrolytic Enzymes ◽  
Ester Hydrolysis ◽  
Enzymic Hydrolysis ◽  
Hydrolysis Products ◽  
Bond Scission ◽  
Micro Organisms ◽  
Hydrolysis Of ◽  
Oxygen Bond ◽  
Comamonas Terrigena

The hydrolysis was studied of potassium (+)-octan-2-yl sulphate by two analogous, optically stereospecific, secondary alkylsulphohydrolases purified from two detergent-degrading micro-organisms, Comamonas terrigena and Pseudomonas C12B. Polarimetry studies have shown that (+)-octan-2-yl sulphate prepared from (+)-octan-2-ol is hydrolysed by both enzymes to yield (-)-octan-2-ol. This inversion of configuration implies that the enzymes are catalysing the scission of the C-O bond of the C-O-S linkage, a type of bond scission apparently not hitherto encountered among hydrolytic enzymes acting on ester bonds. Enzymic hydrolysis of potassium (+)-octan-2-yl sulphate in the presence of H218O and analysis of hydrolysis products for the presence of 18O has confirmed that C-O bond scission (and not O-S bond scission) occurs with both enzymes.

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