Dinitrogen tetroxide-Iodine

Differing from the reaction with dinitrogen tetroxide/iodine (see following section), the addition of nitryl iodide to ( )-l,2-diphenylethylene gave a mixture of diastereomers, as determined by H-NMR spectroscopy129. 

This is surprising, since the reaction of dinitrogen tetroxide with (E)-, 2-diphenylethylene in diethyl ether produced a 3 2 mixture of diastereomeric l,2-dinitro-l,2-diphenylethanes134 The reaction of 2-cholestene with dinitrogen tetroxide/iodine afforded 2/ -iodo-3a-nitro-5oi-chole-stane, this was also the product obtained by the addition of nitryl iodide (see previous section). 

The reaction of dinitrogen tetroxide/iodine gave l-iodo-2-nitrocyclopentane carboxylic acid as the major product (57% yield, undetermined configuration), precursor of the naturally occurring l-amino-2-nitrocyclopentane carboxylic acid135. 

OLEFIN ADDITIONS Benzenesulfonyl azide. Chlorosulfonyl isocyanate. Chiom-ous chloride. Cyanamlde. Dichloroketene. Dinitrogen tetroxide-Iodine. Diphenyl-ketene. Ethoxyketene. Fluoroxytrifluoro-methane. Iodine. Iodine azide. Iodine isocyanate. Iodobenzene dichloride. Mercuric azide. Nitrosyl chloride. Nitrosyl fluoride. Nitryl iodide. Potassium f-but-oxide-Bromoform (dibromocarbene). 

In the photolysis of difiuorodiazirine (218) a singlet carbene was also observed (65JA758). Reactions of the difiuorocarbene were especially studied with partners which are too reactive to be used in the presence of conventional carbene precursors, such as molecular chlorine and iodine, dinitrogen tetroxide, nitryl chloride, carboxylic acids and sulfonic acids. Thus chlorine, trifiuoroacetic acid and trifiuoromethanesulfonic acid reacted with difiuorodiazirine under the conditions of its photolysis to form compounds (237)-(239) (64JHC233). 

The submitters used the following reagents as supplied iodine, ether, and sodium acetate from Mallinckrodt Chemical Works, dinitrogen tetroxide from Matheson Gas Company, and ethyl acrylate from Aldrich Chemical Company, inc. The checkers obtained dinitrogen tetroxide from Matheson Gas Company and the other reagents from Wako Pure Chemical Industries, Ltd., Japan. 

Quinoline Salicylic acid Silicon Dinitrogen tetroxide, linseed oil, maleic anhydride, thionyl chloride Iodine, iron salts, lead acetate Alkali carbonates, calcium, chlorine, cobalt(II) fluoride, manganese trifluoride, oxidants, silver fluoride, sodium-potassium alloy... 

Phenyl-l,2,4-triazoline-3,5-dione has been prepared by oxidizing 4-phenylurazole with lead dioxide,7 and with ammoni-acal silver nitrate followed by an ethereal solution of iodine.8 The yields are low for both methods. 4-Substituted triazoline-diones can also be made by oxidation of the corresponding urazole with fuming nitric acid9 or dinitrogen tetroxide.10 Oxidation by <-butyl hypochlorite in acetone solution has also been described 1112 it, however, yields an unstable product, even after sublimation. Either dioxane12 or ethyl acetate are preferred as solvents for the reaction, since the product is obtained in a stable form. The latter solvent is superior since... 

More direct evidence for the formation of difluorocarbene as an intermediate comes from the photolysis of difluorodiazirine in the presence of chlorine, iodine, dinitrogen tetroxide, and nitryl chloride when the corresponding difluoromethane derivatives were formed, and in the presence of isobutene, buta-l,3-diene, and cis- and frans-but-2-ene when the corresponding 1,1-difluorocyclopropane derivatives were formed. Even with considerable excesses of olefins, appreciable tetra-... 

The high electron dennty of the oxygert atom iti ox nes is favoFaUe to the formation of addition compounds with Lewis acids. Trimethylene oxide has been obeerved to form an iodine complex a hydrate and two dinitrogen tetroxide adducts, one m mole ratio 1 1 and the other 2 The boron fluoride complex is unstable,... 

It reacts with a solution of A2-cholestene in acetonitrile to give 3 -iodo-2/3-hydroxy-cholestane nitrate ester (2). When dinitrogen tetroxide was treated in chloroform with iodine and A2-cholestene was added, the same 3 -iodo-2/3-hydroxycholestane... 

Reaction with olefins. The addition of dinitrogen tetroxide alone is not generally a useful synthetic system because of the formation of several products. However, Stevens and Emmons found that the reaction of dinitrogen tetroxide with an olefin (ether solution, N2) in the presence of excess iodine led to /3-nitroalkyl iodides, usually in good yield ... 

This sequence was used for the synthesis of /-butyinitroacetylene, the first representative of compounds2 of this class. Thus the reaction of dinitrogen tetroxide and iodine with /-butylacetylene (1) gave a mixture of the cis- and trans-isomers (2), which was dehydrohalogenated by distillation from KOH under vacuum. The nitroacetylene is highly reactive as a dienophile, a dipolarophile and an electrophile. It is surprisingly stable to shock and has a half-life of 2-3 days at room temperature. 

Nitroacetamidation of conjugated dienes is efficient when a solution of nitronium tetrafluoroborate in acetonitrile obtained by anodic oxidation of dinitrogen tetroxide is used substantial amounts of both 1,2- and 1,4-adducts are usually obtained.34 Some conjugated nitroalkenes can be readily prepared by reaction of alkenes with sodium nitrite and iodine under mild conditions (Scheme 158).347... 

A wide range of electrophiles have been introduced to the C2 position of the indole ring system via lithio intermediate 24. Electrophiles that have been added include the following (selected examples shown in Table 2) iodine [111, 112] (entry 1), BrCN [112] (entry 2), benzenesulfonyl chloride [112] (entry 3), DMF [14] (entry 4), trimethylsilyl chloride [113] (entry 5), oxirane [114] (entry 6), ketoesters [115,116] (entry 7), allylic halides [117] (entry 8), acyclic anhydrides [106, 109] (entry 9), dinitrogen tetroxide [118] (entry 10), heterocylic carbox-aldehydes [82, 119, 120], heterocylic carbonyl chlorides [92, 94], hetero cyclic... 

---