4,5-dimethyl-10-ethyl- -perchlorate

Hydroxy-3-butenonitrile, see l-Cyano-2-propen-l-ol, 1463 4-Hydroxy-fraws-cinnamic acid, 3130 Hydroxycopper(II) glyoximate, 0795 4-Hydroxy-3,5 -dimethyl-1,2,4-triazole, 1570 4-Hydroxy-3,5-dinitrobenzenearsonic acid, 2213 2-Hydroxy-3,5-dinitrobenzoic acid, see 3,5-Dinitrosalicylic acid, 2661 2-Hydroxy-3,5-dinitropyridine, 1816 N-Hydroxydithiocarbamic acid, 0453 2(2-Hydroxyethoxy)ethyl perchlorate, 1638 (9-(2-Hydroxyethyl)hydroxylamine, 0940... 

DOT CLASSIFICATION 5.1 Label Oxidizer SAFETY PROFILE Moderately toxic by intraperitoneal route. Severe skin and eye irritant. A powerful oxidizer which has caused many explosions in industry. Potentially explosive reactions with alkenes (above 220°C), ammonia, arjl hydrazine + ether, dimethyl sulfoxide + heat, ethylene oxide, fluorobutane + water, organic materials, phosphorus, trimethyl phosphate. Reacts to form explosive products with ethanol (forms ethyl perchlorate), cellulose + dinitrogen tetraoxide + oxygen (forms cellulose nitrate). Avoid contact with mineral acids, butyl fluorides, hydrocarbons. A drying agent. When heated to decomposition it emits toxic fumes of MgO and Cr. See also MAGNESIUM COMPOUNDS and PERCHLORATES. 

ANHYDRONE (10034-81-8) A powerful oxidizer. Potentially violent or explosive reaction with reducing agents, alcohols, ammonia gas, argon (wet), butyl fluorides, dimethyl sulfoxide, ethylene oxide, fluorobutane (wet), fuels, hydrazines, hydrocarbons, mineral acids, powdered metals, organic matter, phosphorus, trimethyl phosphite. Mixture with ethanol forms explosive ethyl perchlorate. Incompatible with alkenes, and many other materials. Shock may cause magnesium perchlorate to explode. 

In a situation where severe steric hindrance e.g., 16,16-dimethyl-20-keto-pregnanes) prevents enol acetate formation, an alternate scheme has been devised. Condensation of ethyl oxalate at C-21 produces, after hydrolysis, the 21-glyoxylic acid this on treatment with acetic anhydride and a strong acid catalyst such as perchloric acid gives both lactone acetates. 

Azatricyclo[2.2.1.02 6]hept-7-yl perchlorate, 2368 f Azetidine, 1255 Benzvalene, 2289 Bicyclo[2.1.0]pent-2-ene, 1856 2-/ert-Butyl-3-phenyloxaziridine, 3406 3 -Chloro-1,3 -diphenyleyclopropene, 3679 l-Chloro-2,3-di(2-thienyl)cyclopropenium perchlorate, 3388 Cyanocyclopropane, 1463 f Cyclopropane, 1197 f Cyclopropyl methyl ether, 1608 2,3 5,6-Dibenzobicyclo[3.3.0]hexane, 3633 3,5 -Dibromo-7-bromomethy lene-7,7a-dihy dro-1,1 -dimethyl-1H-azirino[l,2-a]indole, 3474 2.2 -Di-tert-butyl-3.3 -bioxaziridinc, 3359 Dicyclopropyldiazomethane, 2824 l,4-Dihydrodicyclopropa[ >, g]naphthalene, 3452 iV-Dimethylethyl-3,3-dinitroazetidine, 2848 Dinitrogen pentaoxide, Strained ring heterocycles, 4748 f 1,2-Epoxybutane, 1609 f Ethyl cyclopropanecarboxylate, 2437 2,2 -(l,2-Ethylenebis)3-phenyloxaziridine, 3707 f Methylcyclopropane, 1581 f Methyl cyclopropanecarboxylate, 1917 f Oxetane, 1222... 

Using a typical poly (vinyl chloride) (PVC)-based membrane with different ionophores - Zn-bis(2,4,4-trimethylpen-tyl) dithiophosphinic acid complex [450], protoporphyrin IX dimethyl ester [451], porphyrin derivative [452] and hemato-porphyrin IX [453], tetra(2-aminophenyl) porphyrin [454], cryptands [455, 456], 12-crown-4 [457], benzo-substituted macro-cyclic diamide [458], 5,6,14,15-dibenzo-l, 4-dioxa-8,l 2, diazacyclopentadecane-5,14-diene [459], and (A-[(ethyl-l-pyrrolidinyl-2 -methyl) ] methoxy-2-sulfamoyl-5 -benza-mide [460] - the sensors for zinc ions were prepared and investigated. The armed macrocycle, 5,7,7,12,14,14-hexamethyl-1,4,8,11 -tetraazacyclo tetradeca-4,11 -diene dihydrogen perchlorate was used for the preparation of polystyrene-based Zn(II)-sensitive electrode [461]. 

Ethyl-4-cyanopyridinium perchlorate, AM94 Ethyl diazoacetate, AC8l Ethyl diazoethanoate, AC8l Ethyl trans-3-(N,N-dimethyl-carbamyl)propenoate, A011 Ethylenediamine, ABIO Ethylenediaminetetraacetic acid,... 

Oxybis(Av V-dimethylacetamidetriphenylstibonium) perchlorate, 3905 [l,l -Oxybis[ethane]]tris(trimethyl silyl)aluminium, see Tris(trimethylsilyl)aluminium etherate, 3614 f l,l -Oxybisethene, see Divinyl ether, 1516 2,2 -Oxybis(ethyl nitrate), 1594 f Oxybismethane, see Dimethyl ether, 0915... 

Condensation of dimethylformamide and 2,5-dimethyl-I,3-benzodithio-lium perchlorate in phosphorus oxychloride gives a 2-(2-dimethylamino-vinyl) derivative 199 in excellent yield. A I I condensation product is also obtained from 2,5-dimethyl-I,3-benzodithiolium perchlorate and malono-dialdehydedianilide hydrochloride in hot acetic anhydride. A double condensation between 2-methyl-l,3-dithiolium cations and ethyl orthoformate, leads to 200. 

The parent cation, dissolved in 70% perchloric acid, absorbs with a maximum intensity at 242 and 264 nm (log = 3.80 and 3.55). Introduction of alkyl substituents displaces the longest wavelength peak up to 306 nm in the 4-ethyl-2,5-dimethyl-I,3-dithiolium cation. 

Abbreviations Ac acetyl AIBN azobisisobutyronitrile All allyl Bn benzyl Bz benzoyl ClAc chloroacetyl DAST diethylaminosulfur trifluoride DBU l,8-diazabicyclo[5.4.0]-undec-7-ene DDQ 2,3-dichloro-5,6-dicyano-/)-benzoquinone DMDO dimethyldioxirane DMTST dimethyl(methylthio)sulfonium trifluoromethanesulfonate Fmoc 9-fluorenyl-methoxycarbonyl HDTC hydrazine dithiocarboxylate IDCP iodonium di-collidine perchlorate Lev levulinoyl MBz 4-methylbenzoyl Me methyl MEK methyl ethyl ketone MP 4-methoxyphenyl NBS iV-bromosuccinimide NIS A-iodosuccinimide Pent n-pentenyl Pfp pentafluorophenyl Ph phenyl Phth phthaloyl Piv pivaloyl PMB 4-methoxybenzyl TBAF tetrabutylammonium fluoride TBDMS tcrt-butyldimethylsilyl TBDPS tert-butyldiphenylsilyl TCA trichloroacetyl TES triethylsilyl Tf trifluoromethanesulfonyl TMS trimethylsilyl Tol 4-methylphenyl Tr trityl Troc 2,2,2-trichloroethoxycarbonyl Ts tosyl. 

Voltammetric data for ester reductions are available for several aromatic esters [51-54], and in particular cyclic voltammetry shows clearly that in the absence of proton donors reversible formation of anion radical occurs [51]. In dimethylfonnamide (DMF) solution the peak potential for reduction of methyl benzoate is —2.29 V (versus SCE) for comparison dimethyl terephthalate reduces at —1.68 V and phthalic anhydride at —1.25 V [4]. Half-wave potentials for reduction of aromatic carboxylate esters in an unbuffered solution of pH 7.2 are linearly correlated with cr values [51] electron-withdrawing substituents in the ring or alkoxy group shift Ei/o toward less negative potentials. Generally, esters seem to be more easily reducible than the parent carboxylic acids. Anion radicals of methyl, ethyl, and isopropyl benzoate have been detected by electron paramagnetic resonance (epr) spectroscopy upon cathodic reduction of these esters in acetonitrile-tetrapro-pylammonium perchlorate [52]. The anion radicals of several anhydrides, including phthalic anhydride, have similarly been studied [55]. 

Finally, there are syntheses where the 3 and 4 positions of the triazole become incorporated in a new ring. 4-Amino-5-phenyltriazole, acetylacetone, and sodium hydroxide, when refluxed in ethanol, gave 5,7-dimethyl-3-phenyl-l,2,3-triazolo[3,4-fl]pyrimidine (lOI) (10 min, 91%) (three related examples also cited) [71JCS(C)2156], Similarly, 4-amino-5-phenyltriazole, ethyl acetoacetate, and piperidine, refluxed for 2 hr in ethanol, gave a mixture of 5-methyl-3-phenyl-l,2,3-triazolo[3,4-a]pyrimidin-7(4//)-one (68%) with the 7-methyl isomer (17%) [73JCS(P 1)943], 4-Amino-5-phenyltriazole, condensed with l-methylbut-2-en-l-ol in a mixture of trifluoroacetic and perchloric acids, produced 2,3-diphenyl-l,2,3-triazolo[l,5-a]pyridinium perchlorate (102) (78KGS1422). 

O-Methylation of l,3,5-thiadiazin-2-ones with dimethyl sulfate, followed by treatment with 70% perchloric acid, affords 1,3,5-thiadiazinium perchlorates (e.g. (101 R = Me, X = C104)) in good yields <86ZC132>. Likewise, ethylation with Meerwein s reagent produces the 2-ethoxy-1,3,5-thiadiazinium tetrafluoroborates (e.g. (101 R = Et, X = BF4 81%)). Meerwein s reagent has also been used for the synthesis of 4,6-bis(dialkylamino)-2-ethoxy-l,3,5-oxadiazinium salts from 4,6-bis(dialkylamino)-l,3,5-oxadiazin-2-ones <75S522>. 

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