1.3- dioxol

Chemical Name 5,6,7,8-Tetrahydro-8-hydroxy-7-(hydroxymethyl)-5-(3,4,5-trimethoxy-phenyl)naphtho[2,3/1] -1,3-dioxole-6-carboxylic acid-2-athylhydrazide... 

A detailed spectroscopic and theoretical study of the conformation of dioxolanes 1 has appeared <96T8275>, and a theoretical study has shown that the anomeric effect explains the non-planarity of 1,3-dioxole <96JA9850>. The tetraalkynyldioxolanone 2 has been prepared and its structure and reactivity studied <96HCA634>. Both enantiomers of the chiral glycolic acid equivalent 3 can be prepared from D-mannitol <96HCA1696>, and lipase-mediated kinetic... 

The reaction, formally speaking a [3 + 2] cycloaddition between the aldehyde and a ketocarbene, resembles the dihydrofuran formation from 57 a or similar a-diazoketones and alkenes (see Sect. 2.3.1). For that reaction type, 2-diazo-l,3-dicarbonyl compounds and ethyl diazopyruvate 56 were found to be suited equally well. This similarity pertains also to the reactivity towards carbonyl functions 1,3-dioxole-4-carboxylates are also obtained by copper chelate catalyzed decomposition of 56 in the presence of aliphatic and aromatic aldehydes as well as enolizable ketones 276). No such products were reported for the catalyzed decomposition of ethyl diazoacetate in the presence of the same ketones 271,272). The reasons for the different reactivity of ethoxycarbonylcarbene and a-ketocarbenes (or the respective metal carbenes) have only been speculated upon so far 276). 

H20 (20 ml), CH2Br2 (26 g, 0.15 mol) and Adogen (0.45 g, 1 mmol) are stirred and refluxed briefly under N2. The dihydroxyarene (0.1 mol) and aqueous NaOH are then added dropwise over a period of ca. 2 h. The mixture is stirred and refluxed for a further 1 h. The organic phase is separated and the extracts are washed well with aqueous NaOH (1M) and then with H20 until the washings are neutral. The dried (MgS04) organic phase is evaporated to yield the dioxole [e.g. benzo-1,3-dioxole (76%) from catechol naphtho-[2,3-rf]-1,3-dioxole (82%) from 2,3-dihydroxynaphthalene piperonal (80%) from 2,3-dihydroxybenzaldehyde 4-methylbenzo-1,3-dioxole (86%) from 4-methylcatechol]. 

NOTH Cyclododecan-1, 3,dioxole, 3a alpha, 4,5,6,7,8,9,10,11,12,13,13a beta-dodecahydro-2-methyl... 

Condensation of benzyl glycinate -toluenesulfonate salt with 4,5-diphenyl-1,3-dioxol-2-one affords 154, which can be converted to the 4,5-diphenyl-3-substituted-2(3//)-oxazolones 155 by sequential treatment with an aldehyde/LiHMDS followed by diaminosulfur trifluoride (DAST). Hydrogenolysis then affords the p-fluoro-a-amino acids 156 in excellent yields without any concomitant cleavage of the... 

H fNl F paroxetine 3-(Benzo[1,3]dioxol-5-yloxymethyl)-4-(4-fluoro-phenyl)-piperidine, C19FI2oFN03, MW 329.37, [61869-08-7] headache, migraine (10-50 mg/day for 3-9 months) diabetic neuropathy (40 mg/day for 7 weeks) Black and Sheline, 1995 Sindrup et al., 1990b... 

Reactions of 4,7-phenanthroline-5,6-dione have been the subject of considerable study. It is reduced to 5,6-dihydroxy-4,7-phenanthroline by Raney nickel hydrogenation226,249 or by aromatic thiols in benzene,262 and oxidized by permanganate to 3,3 -bipyridyl-2,2 -dicarboxylic acid.263 It forms bishemiketals with alcohols226 and diepoxides with diazomethane.226 The diepoxides by reaction with hydrochloric acid form diols of type 57, R = Cl, which on oxidation with lead tetraacetate give 3,3 -bipyridyl diketones of type 58, R = Cl. Methyl ketones of type 58, R = H, are also obtained by lead(IV) acetate oxidation of the diol 57, R = H, obtained by lithium aluminum hydride reduction of 57, R = Cl. With phenyldiazomethane and diphenyldiazomethane the dione forms 1,3-dioxole derivatives,264,265 which readily hydrolyze back to the dione with concomitant formation of benzaldehyde and benzophenone, respectively. 

Methylquinoxaline is reported to give a polycyclic derivative (117) related to quinoxaline orange with 2-equivalents of tetrachloro-1,2-ben zoquinone 2-(2-quinoxalino)-4,5,6,7-tetrachlorobenzo-1,3-dioxole... 

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