Mercuric chloride, hydrolysis

The more generally known mercuric oxide-mercuric chloride hydrolysis 2 may also be used, and in the present case it gives a yield of about 90%. The reductive desulfurization of Part E is also based on the work of Mukaiyama.12 It is clearly superior to Raney nickel desulfurization, which gives only 36-45% of 3-benzylindole. 

Hydrolysis of vinyl sulfides to carbonyl compounds. Corey and Shulman (3, 97) in 1970 fhst reported that vinyl sulfides could be hydrolyzed to ketones with mercuric chloride in aqueous acetonitrile. This method, sometimes in combination with mercuric oxide or calcium carbonate (4, 38, 39), has been widely used. However, recently, Grieco, Cohen, and collaborators have reported that mercuric chloride hydrolysis of vinyl sulfides of type (1) to aldehydes is not generally successful. They have found a very simple solution illustrated for hydrolysis of (2) to n-heptanal (4). 

The isothiocyanate (178) was converted to the isothiourea (179), but on treatment with ammonia the nitrile reacted to give a guanidine without replacement of the methylthio group. It was suggested that steric hindrance from the ortAo-chlorines was responsible for this unexpected reactivity. However, the crude salt (180) readily gave (181) when treated with ammonia in the presence of mercuric chloride. Hydrolysis then afforded biclodil (182) Scheme 5.42.) [231]. The compound has been examined as a vasodilator useful in congestive heart failure [232], but is also used to treat coccidiosis [233],... 

A rather special procedure for the preparation of 21-hydroxy-20-ketopreg-nanes starts with the 17a-ethoxyethynyl-17 -hydroxy steroids described earlier. Free radical addition of ethanethiol to the triple bond, followed by acid-catalyzed hydrolysis and dehydration gives the 20-thioenol ether 21-aldehyde. This can be reduced with lithium aluminum hydride to the C-21 alcohol and then hydrolyzed to the C-20 ketone in the presence of mercuric chloride. The overall yield, without isolation of intermediates, is in the order of 50% ... 

The preparation of histidine by the hydrolysis of hemoglobin and precipitation with mercuric chloride in alkaline solution was... 

Addition of l,3-bis(methylthio)allyllithium to aldehydes, ketones, and epoxides followed by mercuric ion-promoted hydrolysis furnishes hydroxyalkyl derivatives of acrolein5 that are otherwise available in lower yield by multistep procedures. For example, addition of 1,3-bis-(methylthio)allyllithium to acetone proceeds in 97% yield to give a tertiary alcohol that is hydrolyzed with mercuric chloride and calcium carbonate to saturated aldehyde.8 Similarly, addition of l,3-bis(methylthio)allyl-lithium to an epoxide, acetylation of the hydroxyl group, and hydrolysis with mercuric chloride and calcium carbonate provides a 5-acetoxy-a,/ -unsaturatcd aldehyde,6 as indicated in Table I. Cyclic cis-epoxides give aldehydes in which the acetoxy group is trans to the 3-oxopropenyl group. 

A catalytic acid hydrolysis, AaCa mechanism, has been implicated in bromination of A-acetyl-A -arylurea, MeCONHCONHCeHtR-j (R = Me, Cl, NO2) in the presence of mercuric chloride. ... 

Alternative methods for removing 1-propenyl groups under non-acidic conditions have been reported these include reaction with alkaline potassium permanganate solution,204,205 ozonolysis followed by alkaline hydrolysis,204 205 treatment with a mercuric chloride-mercuric oxide reagent,206,207 and treatment with palladium on activated charcoal in a hydroxylic solvent containing a trace of an acid.2070 The last procedure is a combined isomerization-hydrolysis, but the isomerization step may be independently achieved by omission of the acid.2070,2076... 

This salt was formerly named mercuriammonium chloride. Prepare a solution of 10 g. of mercuric chloride and to this slowly add a dilute solution of ammonium hydroxide as long as a precipitate is produced, avoiding an excess. Collect the precipitate on a filter, washing it once or twice with water. Too much washing is to be avoided, since the salt turns yellow from hydrolysis. Dry the precipitate on porous paper. 

The jet black colour is produced by the admixture of the finely divided mercury with the white precipitate. With aq. ammonia both hydrolysis and ammonolysis may occur, thus, with mercuric chloride ... 

Phenylthiotrimethylsilane adds to propenoyl trimethylsilane under the influence of Lewis acid to give l,3-bis(phenylthio)-l-trimethylsilylprop-l-ene (18). This enol thioether may be deprotonated with f-butyl lithium and alkylated with any of a large range of electrophiles. Subsequent hydrolysis-elimination with mercuric chloride in aqueous acetonitrile provides -substituted a,/J-unsaturated acyl silanes (vide supra, Section III.D.3)132. It should be noted that, in this transformation, the /1-substituent has... 

A sulfur-containing, septanose form is only obtainable as a result of the protection of the C-5 and C-4 hydroxyl groups in such a way that the pyranose or furanose rings cannot be formed. 2,3,4,5-Tetra-O-acetyl-S-acetyl-6-thio-D-galactose diethyl dithioacetal (273), obtained from the corresponding 6-p-toluenesulfonate with potassium thioacet-ate, undergoes hydrolysis in the presence of mercuric chloride and... 

Reaction of (1) with an aldehyde or ketone followed by hydrolysis furnishes a y-hydroxy-a,)3-unsaturated aldehyde. For example, addition of (I) to propanal forms l,3-bis(methylthio>-l-hcxene-4-ol (4) in 89% yield hydrolysis with mercuric chloride gives franj-4-hydroxy-2-hcxenal (5) in 48% yield. 

Aldehyde synthesis 2,4-Dimethylthiazole (1) when treated with n-butyllithium in dry THF and then with benzyl chloride yields 2-(2-phenylethyl)-4-methylthiazole (2) in 94% yield. This product is then alkylated with trimethyloxonium fluoroborate and reduced with sodium borohydride to give 2-(2-phenylethyl)-3,4-dimcthylthiazolidine (3) in high yield. The final step is hydrolysis using mercuric chloride as catalyst 3-phenyl-propanal (4) is obtained in 60% yield. 

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