Hydrolysis ammonium nitrate

Feldman and Skoumbourdis have utilized an oxidative hydrolysis of the thioimidate with ceric ammonium nitrate (CAN) to generate dibromophakellstatin 78 as the final step in their synthetic sequence (Equation 14) <20050L929>. 

A Greek team also reported on oxidation of partially saturated heterocycles to fully heteroaromatic rings <1996JHC599> 5-/>-anisyl-4,5-dihydro[l,2,3]triazolo[5,l-/][l,2,4]triazine 91, when treated with cerium ammonium nitrate, underwent an oxidative hydrolysis giving heteroaromatic product 92 in poor yield (20%). 

Chapman studied the nitrolysis of symmetrical methylenediamines. The nitrolysis of N, N, N, M-tetramethylmethylenediamine with nitric acid-acetic anhydride-ammonium nitrate mixtures gives both dimethylnitramine and RDX the latter probably arises from the nitroT ysis of hexamine formed from the reaction of ammonium nitrate and formaldehyde released from the hydrolysis of the methylenediamine. The same reaction with some morpholine-based methylenediamines (105) allows the synthesis of l,3,5-trinitro-l,3,5-triazacycloalkanes (106). 

Treatment of the ammonium salt of 3,5-dinitro-1,2,4-triazole (113) with hydrazine hydrate leads to selective reduction of one of the nitro groups to yield 3-amino-5-nitro-1,2,4-triazole (ANTA) (114), a high performance explosive (calculated VOD 8460 m/s) possessing thermal stability (m.p. 238 °C) and an extremely low sensitivity to impact. ANTA (114) is also synthesized from the nitration of 3-acetyl-l,2,4-triazole with anhydrous nitric acid in acetic anhydride at subambient temperature followed by hydrolysis of the acetyl functionality. The ammonium salt of 3,5-dinitro-l,2,4-triazole (113) is itself a useful explosive which forms a eutectic with ammonium nitrate. ... 

Solid-phase synthesis of pyrido[2,3 pytirtiidines 514 was achieved by Hantzsch condensation of Wang resin-supported Knoevenagel derivative 513 with 6-aminouracil derivatives 512 as an a-oxo enamine component in the presence of ceric ammonium nitrate (CAN) in DMA followed by hydrolysis with TFA in CH2GI2. Compound 513 was prepared by treatment of a hydroxylated polymer, such as Wang or Sasrin resin, with diketene, followed by condensation with benzaldehyde (Equation 41) <1996TL4643>. 

Cerium(IV) ammonium nitrate (CAN) is effective for oxidative hydrolysis of phenyl esters substituted by hydroxyl, methoxyl, and dimethylamino groups in CH3CN-H20 at 0°. 

If a mixture of a soln. of the trisodium salt with a slight excess over an eq. proportion of ammonium nitrate be evaporated, ammonia escapes, and the acid soln. is neutralized with ammonia from time to time water is also added if necessary to dissolve any crystals. During the cooling of the hot soln., crystals of sodium ammonium nitratoimidodisulphonate, NH(NH4S03)2.NaN03, are formed in small, flat, thick prisms, which are anhydrous, and stable in air. The salt cannot be washed with water, or recrystallized from water without hydrolysis. If too little ammonium nitrate is used the complex salt is contaminated with some disodium imidosulphonate. The constitution is represented with quinquevalent nitrogen ... 

Protection2 and activation1 of carboxylic acids. Carboxylic acids react with 1 in the presence of a 2-chloropyridinium salt, proton sponge, and DMAP to form amides (2). These amides are stable to acids and bases but deprotection is possible with oxidative hydrolysis with ceric ammonium nitrate (CAN). If the oxidation is carried out in the presence of an amine, an amide is obtained in 70-95% yield. For this purpose, the combination of copper(II) oxide and ceric pyridinium chloride is far superior to CAN.4 No racemization was observed in the benzoylation of an a-amino ester. 

Cerium(IV) ammonium nitrate in aqueous acetonitrile is an alternative oxidant for the cleavage of p-methoxybenzyl ethers.335 Compared with DDQ, it is seldom used336 337 but there are circumstances where it will work when DDQ fails. A case in point is shown in Scheme 4.182.338 The ditosylate 182.1 underwent oxidative hydrolysis in the usual way with DDQ to give the alcohol 18U in 80% yield but attempts to deprotect the monotosylate 182.3 failed under the same conditions. However, with CAN, the monotosylate gave the desired diol 182.4 in 30% yield together with the p-methoxybenzoate 1825 in 24% yield. 

The cleavage of alkenylboranes may be carried out under non-acidic conditions by converting the alkenylborane into the ate complex with n-BuLi prior to hydrolysis with aqueous NaOH. " Also, alkenylboranes derived from internal alkynes may be protonated under neutral conditions using catalytic amounts of Pd(0Ac)2 in THF or acetoneor with aqueous silver ammonium nitrate [Ag(NH3)2 N03]. ... 

The action of n-butyllithium in THF at low temperature leads to the anion. After reaction with an electrophilic compound, e hydrolysis can generally be carried out in polar solvents (acetone, alcohols, acetonitrile) in the presence of mercury(II) chloride or oxide and water.In other cases, NBS, - chloramine T, cerium(IV) ammonium nitrate, n-tributyltin hydride, trialkyloxonium tetrafluorobor-ate, thallium nitrate or photochemistry can be used. Desulfurization by Raney nickel gives hydro-carbons. ... 

Y butenolides 22 were obtained in good yields and as essentially single stereoisomers (Table 5.2). In these studies, the tat leucine derived SchifTbase ligand 18a gave rise to the best diastereo and enantioselectivities, and even with the less expensive valine derived Schiffbase ligand, the products were formed with 97% ee. Removal of the N aryl group was readily accomplished with cerium ammonium nitrate followed by acidic hydrolysis of the intermediate aza quinone. 

One vety useful transfomiation of these adducts is given in equation (75). Hydrolysis of the diester to the diacid, followed by bis>decarboxylation either by a double Curtius rearrangement or oxidatively with ceric ammonium nitrate, yields an unsaturated lactone. This overall sequence is equivalent to effecting a Diels-Alder reaction wiA carbon dioxide, which is unreactive as a dienophile. 

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