Methanesulfonyl Chloride heterocycles

The 1,3-dipolar addition to terminal alkenes of nitrile oxides, generated from nitromethylene derivatives of bicycloheptane, provides 9,ll-ethano-13,15-isoxazolinoprostanoids, PGH analogs, with alkyl, phenyl, or additional heterocyclic fragment in the oo-chain (461). Chemical transformations of 9,11-ethano-13,15-isoxazolinoprostanoids furnish prostanoids with bifunctional fragments of P-hydroxyketone and a-aminoalcohol in the oo-chain. The reaction of P-hydroxy ketones with methanesulfonyl chloride gives rise to prostanoids with an enone component in the oo-chain. 9,ll-Ethano-16-thiaprostanoids have been prepared, for the first time, by nucleophilic addition of thiols to the polarized double bond in the oo-chain. The 1,3-dipolar addition to terminal alkenes of nitrile oxides, generated from nitromethylene derivatives of bicycloheptane provides 9,ll-ethano-13,15-isoxazolinoprostanoids with an alkyl, phenyl, or additional heterocyclic fragment in the oo-chain (462). 

An alternate method for building the partly saturated fused heterocyclic system for ticlopidine (10-4) starts by formation of the mesylate (11-2) from cyanopyridone (11-1) by treatment with methanesulfonyl chloride. The reaction of that with butyl thioglycolate can be envisaged as involving, first, the addition of the thiol group to... 

Phenyl ethylenesulfonate, 241 Tin(IV) chloride, 300 Containing one sulfur 2,4-Bis(4-me thoxyphenyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide, 38 Titanium(IV) chloride-Zinc, 310 Other five-membered heterocycles Carbon dioxide, 65 Methanesulfonyl chloride, 176 Six-membered rings Containing one nitrogen—piperidines Dichlorotris(triphenylphosphine)-ruthenium(II), 107 Mercury(II) trifluoroacetate, 175 Tetrakis(triphenylphosphine)-palladium(O), 289... 

The production of a 2-unsubstituted chromone by this route requires the use of formate, or its equivalent, as the ester a good method for this is the use of triethyl orthoformate the combination dimethylformamide/methanesulfonyl chloride has also been employed. Another route to 2-unsubstituted chromones employs oxalic acid half-ester half-acid chloride, which gives a 2-ethoxycar-bonyl chromone, hydrolysis and decarboxylation of which achieves the required result. Diethyl carbonate as the ester gives rise to 2,4-dioxygenated heterocycles, which exist as 4-hydroxy-coumarins. ... 

Heterocycles. Sulfene, generated by the treatment of methanesulfonyl chloride with base, undergoes [2 + 2], [3 + 2], and [4 + 2] cycloadditions to produce four-, five-, and six-membered heterocycles, respectively. Alkynyl amines and enamines both undergo [2 + 2] cycloadditions with sulfene to produce four-membered cyclic sulfones (eqs 19 and 20). 

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