Potassium substituted derivatives

Phenylethylamme and its substituted derivatives with methoxybutenone in glacial acetic acid afford the salts of the type 236, which, when oxidized with potassium permanganate, decompose to a-pyridone, whereas in an aqueous medium the compound 237 is formed (80MI1 62AG161). 

Besides the technical method starting from naphthalene, phthalic acid and its substituted derivatives can be prepared by oxidation of o-xylene to phthalic acid with potassium permanganate. This compound can be subsequently transformed via an anhydride, imide, and amide to a derivative of phthalonitrile, which is the more convenient starting material for several coordination compounds. The synthesis of the ferf-butyl-substituted dicarbonitrile, which is a very common starting material for highly soluble phthalocyanines, is shown below.97,105... 

The metallation of 1,3-diselenanes is complex. When potassium diisopropylamide is used as base, deprotonation and alkylation affords the 2-equatorially substituted derivative <96TL2667>. However, with rertbutyllithium, Se-Li exchange is observed in preference to H-Li exchange in the reaction with 2-ox-methylseleno derivatives <96TL8015>. The reaction with nBuLi either forms the anion or cleaves a C-Se bond depending on the substituents present at the 2-, 4- and 6- positions <96TL8011>. 

Detailed investigations of the chemical reactivity of the diketiminato-stabilized phosphenium cations like 28 (Scheme 17) are to date rare and include only two reports dealing with the substitution and reduction of P-halogen-derivatives. Thus, reaction of 28 (X=Br) with sodium hydroxide in toluene was reported to proceed with displacement of the halide substituent at phosphorus and conservation of the heterocyclic ring to give a mixture of bromide and triflate salts containing a P-hydroxy-substituted cation, both of which were isolated in small yields [89], The products are remarkable as they represent one of very few examples of a stable phosphinous acid which does not rearrange to the tautomeric secondary phosphine oxide. Potassium reduction of the P-chloro-substituted derivative 34 produced the... 

The reactions of the corresponding propargyl sulfoxides and sulfones now resemble the chemistry of the other acceptor-substituted derivatives such as ketones and aldehydes (see Section 1.2.4). Compared with the thioethers, here much milder bases are sufficient apart from aluminum oxide, often triethylamine or potassium carbonate are used. Sometimes even a spontaneous isomerization takes place. The selective isomerization of one triple bond in the presence of a second triple bond in 126 [313] (Scheme 1.56) or an allyl sulfone in 129 [314] (Scheme 1.57) are just two examples out of a whole series [178, 304, 313, 315-331]. When, on the other hand, the in situ oxidation of 126 was carried out in an aprotic solvent, no isomerization at all was observed. 

The highly substituted derivative 186, in the form of the potassium salt, has been recommended for use in detonators in place of the more dangerous mercury fulminate. l,2,3-Benzotriazine-4-thione (39, R — H) has been used in photographic transfer emulsions as an inhibitor and toning agent, and heavy metal salts of the oxygen analog 10, R = H are employed as photodevelopable emulsions. The latter compound is also claimed to be useful as a stabilizer in olefin polymers and as an antioxidant in certain other polymers. Dimeric derivatives of 10 have... 

Reaction of the potassium salt of the [l,2,3]triazolo[4,5-d [l,2,5]oxadiazole 2-oxide 68 with AgNOs furnished the corresponding silver salt whilst the parent bicycle was obtained on acidification < 1996TL8577 >. Methylation of either the silver salt, or the parent bicycle, led to mixtures of the IV- and 0-methylated derivatives 67 and 69. In each case the selectivity of the reaction differed, the parent showed a 9 1 preference for the A-substituted derivative however, the 0-methylated product dominated and 67 and 69 resulted in a 4 3 ratio in the reaction starting from the silver salt (Scheme 5) <1996TL8577>. 

Dinitro[l,8]naphthyridine and its 2-substituted derivatives are dehydro-methylaminated with a solution of potassium permanganate in liquid methylamine to afford the corresponding mono- or bis-methylamino-3,6-dinitro[l,8]naphthyridines (Scheme 7) <2000CJC950>. When the 2-substituent is either chlorine or OMe, then some substitution by NHCH3 also occurs. Quantum-chemical calculations have shown that the reaction is controlled by the interaction of the frontier MOs. 

F-marked potassium fluoride has been prepared and used to convert ethyl 2-bromo-propanoate (11) to the corresponding l8F-substituted derivative 12.50... 

C-Alkylation of 1-methyl-1,2,3,4-tetrahydro-6//-pyrimido[l,2-b]isoquino-lin-6-one with benzyl bromide in boiling methylene chloride overnight in the presence of potassium carbonate, and with excess methyl iodide gave 11-substituted derivatives (113 and 114) (88HCA77). The treatment of hydrobromide salt of 11-benzyl derivative 113 with a base yielded 11-benzyl-1 -methyl-1,2,3,4-tetrahydro-6//-pyrimido[l, 2-6]isoquinolin-6-one (115). 

The first type of acid to be dealt with contains the selenocyano-grouping —SeCN. This is introduced into aliphatic acids by treating their halogen-substituted derivatives with potassium selenocyanate in the presence of potassium hydroxide, e.g. ... 

When a solution of 1-aminopyridinium iodide (143) in DMF was treated with anhydrous potassium carbonate, the mixture developed the deep blue color characteristic of pyridine 1-imine (144) addition of EP caused an immediate exothermic reaction giving the pyrazolopyridine 145 in 48% yield311 hydrolysis and decarboxylation gave a high yield of pyrazolo[l,5-a]pyridine (146).311 Many reactions of this type have now been carried out,312 and the regioselectivity for the cydization of 3-substituted derivatives has been examined,313... 

Dehydrohalogenation of (bromomethyl)cyclohexane with potassium ferf-butoxide, a sterically hindered and strong base, would give the desired alkene as the major product. The substitution derived from SN2 displacement of the halide by the alkoxide might also be obtained as a minor product. 

It was shown (78JFC(12)193) that the product of the reaction of perfhioro-2-methylpent-2-ene with potassium ethyldithiocarbamate in dimethylformamide is 5,5-bis(trifhioromethyl)-5-(tetrafluoroethylidene)-2-fhioro-2-ethoxy-l,3-dithiolane. Analogously, the reaction of 1,1,1-trifluoro-methyl-2-bromoprop-2-ene with thiourea and its N-substituted derivatives yields 5-trifhioromethyl-2-thione-thiazolidines 57 (92JFC(58)365). 

Treatment of 1 //-pyrrolo[2,3-7>]pyridine (1) with mesitylenesulfonylhydroxylamine resulted in Anamination of the pyridine nitrogen in high yields. Upon addition of a base such as potassium hydroxide the ylide which formed rapidly underwent tautomerization to give 7-ami no-7//-pyrrolo[2,3-A]pyridine in nearly quantitative yields. For some substituted derivatives, which did not undergo tautomerism, diazepines were formed upon irradiation. The diazepines were too unstable to be isolated <79CPB2183> (see Section 7.06.5.1.2). 

The reaction of amidines with sodium hypochlorite and potassium thiocyanate (Scheme 145) is a mild method for producing a variety of 5-amino- and 3,5-diamino-1,2,4-thiadiazoles (16) in good yields (also see Scheme 98) (65AHC(5)119). Af-substituted derivatives are obtained when isothiocyanates (RCNS) are used in place of potassium thiocyanate (78USP4107377). 

Cyclic sulfamates 47 can be smoothly transferred into the corresponding N-substituted derivatives 48a and 48b in the presence of potassium carbonate in DMF (Scheme 8 <2005OL4685>). 

---