Hydroperoxides acyl, preparation

Alkoxyall l Hydroperoxides. These compounds (1, X = OR , R = H) have been prepared by the ozonization of certain unsaturated compounds in alcohol solvents (10,125,126). 2-Methoxy-2-hydroperoxypropane [10027-74 ] (1, X = OR , R" = methyl), has been generated in methanol solution and spectral data obtained (127). A rapid exothermic decomposition upon concentration of this peroxide in a methylene chloride—methanol solution at 0°C has been reported (128). 2-Bromo-l-methoxy-l-methylethylhydroperoxide [98821-14-8]has been distilled (bp 60°C (bath temp.), 0.013 kPa) (129). Two cycHc alkoxyaLkyl hydroperoxides from cyclodecanone have been reported (1, where X = OR R, R = 5-oxo-l, 9-nonanediyl) with mp 94—95°C (R" = methyl) and mp 66—68°C (R" = ethyl) (130). Like other hydroperoxides, alkoxyaLkyl hydroperoxides can be acylated or alkylated (130,131). 

Diacyl peroxides and acyl hydroperoxides can similarly be prepared from acyl halides or anhydrides... 

Masakatsu Shibasaki of the University of Tokyo reports (J. Am. Chem. Soc. 2004,126, 7559) that use of a BINOL-derived catalyst with cumyl hydroperoxide enables the enantioselective epoxidation of unsaturated N-acyl pyrroles such as 7. The pyrroles 7, prepared from the precursor aldehydes such as 5 with the reagent 6, can be used directly, without further purification. 

Peroxycarboxylic acid esters are utilized as initiators for radical polymerization and are interesting intermediates for the decarboxylation of carboxylic acids. They are generally prepared by the acylation of hydro peroxides with acid chlorides, acid anhydrides, or imidazolides in the presence of a base. Condensation of carboxylic acids (20) with /-butyl-hydroperoxide (21) has been smoothly achieved by the use of diethyl phophorocyanidate and NEt3 under mild conditions giving f-butyl peroxycarboxylates (22) in good yield.9... 

There was further study of indole-2,3-epoxides and indole-2,3-dioxetanes. Dioxetanes can be isolated from 1-acyl indoles by photo-oxygenation and are accompanied by more stable hydroperoxides. The oxetanes can be converted to indole-2,3-epoxides by deoxygenation with dimethyl sulfide. <94J0C2733, 94JCS(P2)1503> The epoxides can also be prepared by oxidation of 1-acyl-indoles by dimethyldioxirane. The indole-2,3-epoxides... 

Two mild and metal-ffee methods for the preparation of two types of benzothiazole derivatives (2-acylbenzothiazoles 86 and dialkyl benzothiazol-2-ylphosphonates 87) have been developed (14JOC8407). One method uses tert-butyl hydroperoxide (TBHP) which triggers a-carbon-centered phosphite radical formation, while the other involves di-tert-butyl peroxide (DTBP) which induces phosphorus-centered phosphonate radical formation. The two types of radicals lead to two different reaction pathways direct C2-acylation of benzothiazoles to give 86 and C2-phosphonation of ben-zothiazoles to afford 87. 

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