Mercury II acetate

Mercuration. Mercury(II) salts react with alkyl-, alkenyl-, and arylboranes to yield organomercurials, which are usehil synthetic intermediates (263). For example, dialkyhnercury and alkyhnercury acetates can be prepared from primary trialkylboranes by treatment with mercury(II) chloride in the presence of sodium hydroxide or with mercury(II) acetate in tetrahydrofuran (3,264). Mercuration of 3 -alkylboranes is sluggish and requires prolonged heating. Alkenyl groups are transferred from boron to mercury with retention of configuration (243,265). 

Mercury(II) acetate tends to mercurate all the free nuclear positions in pyrrole, furan and thiophene to give derivatives of type (74). The acetoxymercuration of thiophene has been estimated to proceed ca. 10 times faster than that of benzene. Mercuration of rings with deactivating substituents such as ethoxycarbonyl and nitro is still possible with this reagent, as shown by the formation of compounds (75) and (76). Mercury(II) chloride is a milder mercurating agent, as illustrated by the chloromercuration of thiophene to give either the 2- or 2,5-disubstituted product (Scheme 25). 

Benzo[h]thiophene sulfone (229) reacts as a vinyl sulfone and forms adducts (228) and (230) when treated with mercury(II) acetate in methanol and with cyclopentadiene, respectively. 

The employment of non-protic electrophiles for the foregoing type of cyclizations as illustrated in Scheme 8 has the particular merit of leaving a useful point of departure for further transformations. Comparable cyclizations of 2-allyl-3-aminocyclohexenones with mercury(II) acetate are preceded by dehydrogenation to the corresponding 2-allyl-3-aminophenol as shown in Scheme 9 82TL3591). The preferred direction of cyclization depends upon the nucleophilicity of the amino group. 

A -Pyrazolines such as (410) are oxidized by iodine, mercury(II) acetate and trityl chloride to pyrazolium salts (411), and compound (410) even reduces silver nitrate to Ag° (69JOU1480). Electrochemical oxidation of l,3,5-triaryl-2-pyrazolines has been studied in detail (74BSF768, 79CHE115). They Undergo oxidative dimerization and subsequent transformation into the pyrazole derivative (412). 

Analogous to the oxidation of hydrazones to azo compounds, A-unsubstituted pyrazolidines are oxidized to A -pyrazolines. For example, the blcyclic pyrazolidine (415) when treated with silver oxide yields the pyrazoline (416) (65JA3023). Pyrazolidine (417) is transformed into the perchlorate of the pyrazolium salt (411) by reaction with mercury(II) acetate in ethanol followed by addition of sodium perchlorate (69JOU1480). 

Electrophilic mercuration of isoxazoles parallels that of pyridine and other azole derivatives. The reaction of 3,5-disubstituted isoxazoles with raercury(II) acetate results in a very high yield of 4-acetoxymercury derivatives which can be converted into 4-broraoisoxazoles. Thus, the reaction of 5-phenylisoxazole (64) with mercury(II) acetate gave mercuriacetate (88) (in 90% yield), which after treatment with potassium bromide and bromine gave 4-bromo-5-phenylisoxazole (89) in 65% yield. The unsubstituted isoxazole, however, is oxidized under the same reaction conditions, giving mercury(I) salts. 

Dibenzosubeiyl alcohol reacts in 60% yield with cysteine to give a thioether that is cleaved by mercury(II) acetate or oxidized by iodine to cystine. The dibenzo-suberyl group has also been used to protect —OH, —NH2, and —CO2H groups. ... 

Benzamidomethyl-A -methylcysteine has been prepared as a crystalline derivative (H0CH2NHC0C6H 5, anhydr. CF3CO2H, 25°, 45 min, 88% yield as the tri-fluoroacetate salt) and cleaved (100% yield) by treatment with mercury(II) acetate (pH 4, 25°, 1 h) followed by hydrogen sulfide. Attempted preparation of S-acetamidomethyl-N-methylcysteine resulted in noncrystalline material, shown by TLC to be a mixture. ... 

The removal of an 5-benzylthiomethyl protective group from a dithioacetal with mercury(II) acetate avoids certain side reactions that occur when an S-benzyl thioether is cleaved with sodium/ammonia. The dithioacetal is stable to hydrogen bromide/acetic acid used to cleave benzyl carbamates. 

Merkuri-. mercuric, mercuri-, mercury(II). Merkuriah en, pi. Pharm.) mercurials. Merkuriahnittel, n. Pharm.) mercurial. Merkuri-ammoniumchlorid, n. mercuriammo-nium chloride, -azetat, n. mercuric acetate, mercury(II) acetate, -chlorid, n. mercuric chloride, mercury(II) chloride, -cyamd, n. mercuric cyanide, mercury(II) cyanide, -cyanwasserstoffs ure, /. mercuricyanic acid, cyanomercuric(II) acid. 

Vinyl acetate was originally produced hy the reaction of acetylene and acetic acid in the presence of mercury(II) acetate. Currently, it is produced hy the catalytic oxidation of ethylene with oxygen, with acetic acid as a reactant and palladium as the catalyst ... 

In the laboratory, alkenes are often hydrated by the oxymercuration procedure. When an alkene is treated with mercury(II) acetate Hg(02CCH3)2, usually abbreviated Hg(OAc)2l in aqueous tetrahydrofuran (THF) solvent, electrophilic addition of Hg2+ to the double bond rapidly occurs. The intermediate orgnnomercury compound is then treated with sodium borohydride, NaBH4, and an alcohol is produced. For example ... 

Reaction of cyclohexene with mercury(II) acetate in CH3OH rather than H20, followed by treatment with NaBH4, yields cyclohexy) methyl ether rather than cyclohexanol. Suggest a mechanism. 

Notes 1, Gold anode 2, silver anode 3, mercury anode 4, mercury cathode for reagent see footnote J 5, trace of mercury(II) acetate dissolved in acetic acid/methanol mixture added as catalyst, t A, amperometric I, indicator P, potentiometric. 

Mercuration of trithiadiazepine 4 with mercury(II) acetate in acetic acid gives 6,7-bis(acetoxymercurio)trithiadiazepine 12, accompanied by a small amount of the product 13 of monosubstitution.387... 

The reaction of 6-nitrotrithiadiazepine 5 with mercury(II) acetate unexpectedly yields bis-(7-nitrotrithiadiazepin-6-yl)mercury 17, which gives 6-iodo-7-nitrotrithiadiazepine 18 on treatment with iodine.387... 

S-Acetamidomethyl-L-cysteine hydrochloride Alanine, 3-[(acetamidomethyl)thio]-, monohydrochloride, i- (8) L-Cysteine, S-[(acetylamino)methyl]-, monohydrochloride (9) (28798-28-9) L-Cysteine hydrochloride, monohydrate (8, 9) (7048-04-6) Mercury(II) acetate Acetic acid, mercury (2) salt (8,9) (1600-27-7)... 

The organo-corrinoids show similar behavior, but also additional complications. Rate constants have been determined 84) for the attack of mercury(II) acetate on various organocobalt cobinamides (X = H2O or absent) and cobalamins (X = 5,6-dimethylbenziminazole). The first complication, which has to be born in mind when comparing the cobinamides with the cobalamins or DMG complexes, is that the organocobin-amides are partly (R = vinyl and methyl) or wholly (R = Et, -Pr, t-Pr,... 

Redox titrants (mainly in acetic acid) are bromine, iodine monochloride, chlorine dioxide, iodine (for Karl Fischer reagent based on a methanolic solution of iodine and S02 with pyridine, and the alternatives, methyl-Cellosolve instead of methanol, or sodium acetate instead of pyridine (see pp. 204-205), and other oxidants, mostly compounds of metals of high valency such as potassium permanganate, chromic acid, lead(IV) or mercury(II) acetate or cerium(IV) salts reductants include sodium dithionate, pyrocatechol and oxalic acid, and compounds of metals at low valency such as iron(II) perchlorate, tin(II) chloride, vanadyl acetate, arsenic(IV) or titanium(III) chloride and chromium(II) chloride. 

Another synthetic route to 3-methylhasubanan (43), proposed by Lattes et al. (74), consists of the intramolecular aminomercuration (75) of amino-ethylphenanthrene 27. The key intermediate 27 was treated with mercury(II) acetate in THF/water to yield 9-acetoxymercury-3-methoxyhasubanan (46), as depicted in Scheme 3, and then the reaction product 46 was successively treated with benzyltriethylammonium chloride, sodium hydroxide, and sodium borohydride to furnish the target, 3-methylhasubanan (43) (74). 

Hiller and Funke obtained easily dissolvable linear macromolecules of PVS by anionic polymerization of 1,4-DVB up to conversions of 80-90% [230,231]. In these experiments very low concentrations of n-butyl lithium (n-BuLi) were used and tetrahydrofuran (THF) as solvent. The reactions were carried out at -78 °C and for 7 min. The contents of pendant vinyl groups in the polymer were determined by infrared spectroscopy, mercury-II-acetate addition and catalytic... 

Fig. 47. Conversion of pendant vinyl groups (PV) in 1,4-DVB microgels shown as a function of the reaction time with mercury-II-acetate [230]. Initial monomer and initiator concentrations used for the synthesis of the microgels are 30 g/L and 4 mol % respectively. 

Direct oxidation of oximes is prospective promising procedure for the generation of nitrile oxides. Mercury(II) acetate (54), dimethyldioxirane (55), ceric... 

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