Iodine isocyanate alkenes

Table 3. Carbamates by Addition of Iodine Isocyanate Alkenes...

The alkene pseudohalogen adducts (15) of Scheme 8 are also useful intermediates for aziridine synthesis. These adducts are discussed later in Sections 3.S.6.2-4. The iodine azide and bromine azide adducts may be reduced to aziridines with many reagents recent references report use of lidiium aluminum hydride - and dimethylamineborane. The iodine isocyanate aziridination continues to prove useful, as in Scheme Since the recent reviews, - the mechanism of the triphenylphosphine-based... 

Iodine isocyanate, preformed or made in situ from AgNCO and h, adds to alkeites - with the regio- and stneo-chemistry expected of reactions proceeding via cyclic iodonium ions. When the INCO is made in situ, a competing mechanism also occurs (except with the most reactive alkenes) in which the alkene complexes with the iodine, and the complex then reacts with the isocyanate ion to generate the same P-iodoisocyanate as obtained firom INCO direct The reaction can be carried out at -35 to +20 C in Et20, CHzCh, THF, pentane or excess alkene as solvent. Dichloromethane or ether are... 

A modifi work up of the alkene-iodine isocyanate adducts (Section 3.S.6.4), yields imidazolinones (Scheme 44). ... 

Iodine isocyanate, prefonned or made in situ from AgNCO and I2, adds to alkenes with the... 

The analogous reactions of alkenes with halogen azides are treated in Section 7.2.2 and those with iodine isocyanate and bromocyanamide are treated in Section 7.2.6. 

J-Iodo isocyanates were obtained by addition of iodine isocyanate or thiocyanate to al-kenes45 61. Iodine isocyanate is generated by adding iodine to a suspension of silver cyanate in diethyl ether at — 15°C. When an alkene is present in the reaction medium, anti addition takes place and /J-iodo isocyanates result in good yield52. 

Episulfides. Hinshaw reasoned that addition of an alkene to such solutions should give jS-iodothiocyanates in analogy with the reaction of iodine isocyanate (1, 501 2, 223-224 . 3, 161 -16.3) with alkenes. indeed treatment of cyclohexene with iodine thiocyanate gives a /5-iodothiocyanate (2), which on treatment with methanolic... 

The /i-iodoisocyanate obtained by addition of iodine isocyanate to alkenes can be transformed into aziridines via carbamates, amine salts, or bisulfite addition compounds <67JOC540>. 

Addition to alkenes. The addition reaction of iodine isocyanate to alkenes is much faster in methylene chloride than in ether, the commonly used solvent. The... 

Aziridines can be obtained from alkenes using iodine isocyanate or iodine azide. The product from the latter reaction can be converted into the aziridine via reduction, or into an azirine via elimination of hydrogen iodide and pyrolysis. " ... 

Aziridines are formed from alkenes in a number of multistep processes involving initial reaction with iodine azide, iodine isocyanate or NN-dichlorourethane ... 

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