Our paper reports on the reactivities and orientations of two common phenols, phenol (2) and m-cresol (3), and some of their chlorinated intermediates with aqueous monochloramine, NH2Cl, and dichloramine, NHCl2. We also examined the further reactivity of 2,4,6-trichlorophenol (4) with the chloramines. The phenols are an important area of investigation because they are substituents in the humic acids and are common contaminants in water. m-Cresol (3) was found to be more reactive than phenol (2)with both chlorinating agents. Both NH2Cl and NHCl2were sufficiently reactive to chlorinate all positions ortho and para to the hydroxyl groups. Mono- and dichloramine showed the same orientation with 2 but different orientations in their reactions with the substituent phenols. Indophenol (as its salt) was formed to a minor extent at high pH but not at pH 9. Both NH2Cl and NHCl2 rapidly replaced the parachlorine in 2,4,6-trichlorophenol (4) to give a mixture of 2,6-dichloro-1,4-benzoquinone-4-(N-chloro) imine (5) and 2,6-dichloro-1,4-benzoquinone (18). Similar reactions occurwith 2,4,6-trichloro-m-cresol (17) and 2,4,6-trichloro-3-methoxyphenol (29). The products for 17 were confirmed by mass spectrometry (El and Cl), 1H NMR, 13C NMR, and IR; the products for 29 were confirmed by mass spectrometry (El and Cl) and IR. An ion radical mechanism is suggested to account for the chlorine replacement by the chloramines. [No side chain oxidation of the methyl group in 17 in H20 or ether occurred, with or without ultraviolet radiation.] Both 5 and 18 underwent further chlorination with NH2Cl or NHCl2. Imine 5 did not function as a chlorinated agent.

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Xenon difluoride (XeF2) reacts with methanol to form an unstable reactive species CHgOXeF (1). Formaldehyde is produced quantitatively by disproportionation in the absence of unsaturated hydrocarbons or with unreactive alkenes. Hydrogen fluoride generated in situ complexes with 1 to form 2 which reacts with unsaturated hydrocarbons of intermediajte reactivity such as cisor trtms-l-phenylpropene (5c, 5t), indene (6), 2,3-dimethyl-l,3-butadiene (7), and norbornene (8) as an apparent fluorine electrophile and Markovnikov fluoromethoxy products are found.Reaction of XeF2 with methanol in the presence of boron trifluoride as catalyst forms the complex 3 which disproportionates to formaldehyde. Intermediate 3 reacts with unsaturated hydrocarbons of intermediate reactivity (5c, 5t, 6, 7, and 8) as a positive oxygen electrophile to give anti-Markovnikov fluoromethoxy products. However, very reactive (electron rich) alkenes such as dihydropyran ( 9) react rapidly with XeF2 to give a carbocation species before the intermediate 1 (or its complex 2 or 3) can be formed.Recently1® we reported on the methanolysis of xenon

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The electrophiles bromine, bromine chloride, chlorine, acetyl hypochlorite, and acetyl hypobromite all yield substantial cis addition product by reaction with indene (1) in aprotic solvents, showing that the direct syn collapse of ion pairs obtained from bromine and similar electrophiles is readily possible. The cis to trans ratios with the halogens (but not with the acyl hypohalites) vary with solvent polarities. In the low-polarity solvents (hydrocarbons and carbon tetrachloride) much more syn addition occurs at high halogen concentration. Syn addition of the above electrophiles to 1 as well as methyl hypobromite and methyl hypochlorite was also observed in methanol and acetic acid, with the exception of bromination in methanol where only the trans-dibromide was obtained.

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An investigation of the aqueous chlorination (NaOCl) of resorcinol is reported. The following intermediates were detected in moderate to high yield at different pH values and varying percentages of chlorination: 2-chloro-, 4-chloro-, 2,4-dichloro-, 4,6-dichloro-and 2,4,6-trichlororesorcinol. Only trace amounts of the intermediates were detected when the chlorination was conducted in the presence of phosphate buffer. This result has significant implications since resorcinol in phosphate buffer has been used as a model compound in several recent studies on the formation of chlorinated hydrocarbons during chlorination of drinking water. Relative rates of chlorination were determined for resorcinol and several of the chlorinated resorcinols. Resorcinol was found to chlorinate only three times faster than 2,4,6-trichlororesorcinol. The structure 2,4,6-trichlororesorcinol was established as a monohydrate even after sublimation. A tetrachloro or pentachloro intermediate was not detected, suggesting that the ring-opening step of such an intermediate must be rapid.

Concerted reactions are indicated for the electrophilic addition of chlorosulfonyl isocyanate with monofluoroalkenes. A vinyl fluorine atom on an alkene raises the energy of a stepwise transition state more than the energy of the competing concerted pathway. This energy shift induces CSI to react with monofluoroalkenes by a one-step process. The low reactivity of CSI with monofluoroalkenes, stereospecific reactions, the absence of 2:1 uracil products with neat fluoroalkenes, and quantum chemical calculations support a concerted pathway.