Hypochlorite, r-butyl

Pyridazine-3,6-diones (diazaquinones) are prepared from cyclic hydrazides by oxidation with lead tetraacetate or other oxidizing agents, such as r-butyl hypochlorite, chlorine or nickel peroxide. 

In a similar manner to the formation of pyridazines from AT-aminopyrroles, cinnolines or phthalazines are obtainable from the corresponding 1-aminooxindoles or 2-amino-phthalimides. If the relatively inaccessible 1-aminooxindoles are treated with lead tetraacetate, mercuric acetate, r-butyl hypochlorite (69JCS(C)772) or other agents, cinnolones are formed as shown in Scheme 105. The reaction was postulated to proceed via an intermediate... 

In comparison to N—S bond formation, O—N bond formation by essentially oxidative procedures has found few applications in the synthesis of five-membered heterocycles. The 1,2,4-oxadiazole system (278) was prepared by the action of sodium hypochlorite on A(-acylamidines (277) (76S268). The A -benzoylamidino compounds (279) were also converted into the 1,2,4-oxadiazoles (280) by the action of r-butyl hypochlorite followed by base. In both cyclizations A -chloro compounds are thought to be intermediates (76BCJ3607). 

Diaziridinimines were made analogously. Tri-t-butylguanidine (281) with r-butyl hypochlorite gave (176) in 80% yield. (281) itself is a sufficiently strong base to deprotonate its Af-chloro derivative (69AG(E)448). This procedure also works with methyl- or phenyl-substituted guanidines. 

Cyclic ADC compounds are similarly prepared by oxidation of the corresponding cyclic hydrazine derivatives. The most commonly encountered compounds are the 3//-l,2,4-triazole-3,5(4//)-diones (5), and in particular the 4-phenyl derivative (5, R = Ph), usually abbreviated as PTAD. Similarly, the abbreviation MTAD is used for the 4-methyl derivative. First prepared by Thiele,18 PTAD remained unused in organic synthesis until Cookson reported its powerful dienophilic properties some 70 years later.19 PTAD is an isolable, red, crystalline compound, prepared by r-butyl hypochlorite oxidation of 4-phenylurazole.20 Other oxidants which have been successfully... 

Benzyl methyl Y-substituted benzyl phosphites (280) react in CCI4 at low temperature (-20 to 40 °C) with r-butyl hypochlorite (279) to give a complex mixture of products. Tetraalkoxyphosphonium chlorides (281 At = YC6H4) are the key intermediates, and it is proposed that they can undergo heterocyclic fragmentation in five different ways (Scheme 30). ... 

Conceptually hydrolyze the O to the heteroatom bond while adding an H to the O and an OH to the heteroatom, (a) (CH3),COH and HOCl, r-butyl hypochlorite, (b) CH,CH,OH and HONOj, ethyl nitrate. Tert-butyl hypochlorite is used to chlorinate hydrocarbons by free-radical chain mechanisms. 

Diazirines 7 are usually produced by the Graham procedure (Scheme 6) <1965JA4396> or by the oxidation of N-unsubstituted diaziridines using silver oxide or tert-butyl hypochlorite as oxidants . For example, the unstable diaziridines 10, which can be generated from aldehydes 8 by a modified Schmitz reaction, are converted in situ to diazirines 9 by oxidation with / r/-butyl hypochlorite (Scheme 7) <2000TL795>. 

When subjected to the Conia modification of the Simmons-Smith reaction or cuprous chloride-catalyzed diazomethane decomposition, triquinacene was converted to two monocyclopropanated, two doubly cyclopropanated, and two triply cyclo-propanated products.403) Subsequent photochlorination of 454 with r-butyl hypochlorite at —50 °C has been shown to proceed with ring expansion and formation of 455.404) In contrast, //-exo-trishomotriquinacene (456) could be converted to trichloride 457 with retention of the hexacyclic carbon framework 04)... 

Several medio are available for the intnxluction of sulfenyl groups a to carbonyl derivatives and these have been reviewed. - The most versatile procedure involves reaction of the enolate with an appropriate thiol derivative, but the preferred m od is largely dependent on the nature of the substrate employed (see below). In most instances, sulfur has been introduced in the divalent state and subsequently oxidized, although the oxidative step has been avoided by the direct introduction of sulfur at the S oxidation level. The oxidation of sulfides to sulfoxides is a trivial procedure that can be effected by a variety of reagents. Sodium metaperiodate, m-chloroperbenzoic acid and hydrogen peroxide are the most common oxidants, but r-butyl hydroperoxide, r-butyl hypochlorite, N-chlorobenzotriazole,... 

The ene- pe chlorination, specific with this halogen atom, of alkenes would account for a somewhat different mode of halogen addition, giving usefiil allylic dilorides. Efficient and convenient reagents and methods develtqted are dichlorine monoxide (ChO equation 36), r-butyl hypochlorite, and electro-chemical reactions with chloride ion (equation 37). The ene-type chlorination proceeds smoothly with... 

Nitriles are also the usual products of oxidation of aliphatic amines RCH2NH2 by nickel peroxide and lead(IV) acetate. Aliphatic azo compounds can be prepared from these primary amines by first converting them into ulfamides (6), these then being oxidized with sodium hypochlorite or (better) r butyl hypochlorite (Scheme 9). A few aliphatic azo compounds can be formed in good yield by direct oxidation of r-alkylamines for example, AIBN was formed (86%) by oxidation of the amine Me2C(CN)NH2 with sodium hypochlorite. A special case of azoalkane foimation is the synthesis of chlorodiazirines (7) from amidines RC(= NH)NH2 by oxidation with sodium hypochlorite. ... 

The oxidation of 1,1-disubstituted hydrazines can be achieved by a wide range of oxidants. The oxidative removal of hydrogen formally leads to the production of aminonitrene, or 1,1-diazene, intermediates and many products of such reactions have been interpreted as being derived from aminonitrene intermediates. Indeed, several of these species, derived from sterically hindered hydrazines by oxidation with nickel peroxide or r-butyl hypochlorite, have been detected and characterized in solution at low temperature. Examples include the diazenes (14) and (15). The diazene (16) is stable enough to persist in solution at room temperature for several days. ... 

Methods for the chlorination of secondary amines, secondary amides and imides have been reviewed. Secondary alkylamines can be chlorinated by r-butyl hypochlorite at low temperature, or by sodium hypochlorite or iV-chlorosuccinimide. A(-Bromination and A(-iodination can be brought about using the appropriate halogen, but these N-halodialkylamines are unstable and are rarely isolated. A(-Flu-oroamines and Mfluoroamides are also rare. The A(-fluoroimide (CP3S02)2NF, has, however, been prepared by direct fluorination widi fluorine. It is a stable liquid which shows promise as a fluorinating agent for aromatic compounds. ... 

V-Qiloroaziridines (35) ate configuratiotuilly staUe, and there have been attempts to prepare them in optically active form 1 carrying out the chlorination with r-butyl hypochlorite or widi A(-chlotosuccin-imide in the presence of the optically active alcohol (S)-(+)-HiCH(OH)C F3. Optical yields were, however, low (less than 10% ee). 

Several oxidants have been used to produce the highly reactive cyclic azocaibonyl compounds (39) from the corresponding hydrazides." These include r-butyl hypochlorite, dinitrogen tetroxide and A/-bromosuccinimide. Anodic oxidation and oxidation by iodosylbenzene diacetate are also effective for preparing these and related azocarbonyl compounds. 

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