Iodine isocyanate

Iodine isocyanate was used to synthesize the first steroidal aziridine, 2, 3 -iminocholestane (95). from 5a-cholest-2-ene (91). This reaction sequence which is believed to proceed through a three-membered ring iodonium ion (92) illustrates the limitation of pseudohalogen additions for the synthesis of -aziridines. The iodonium complex forms from the least hindered side (usually alpha) and is opened tmK5-diaxially to give a -oriented nitrogen function. The 3a-iodo-2 -isocyanate (93) is converted by treatment with... 

Iodine azide, on the other hand, forms pure adducts with A -, A - and A -steroids by a mechanism analogous to that proposed for iodine isocyanate additions. Reduction of such adducts can lead to aziridines. However, most reducing agents effect elimination of the elements of iodine azide from the /mwj -diaxial adducts of the A - and A -olefins rather than reduction of the azide function to the iodo amine. Thus, this sequence appears to be of little value for the synthesis of A-, B- or C-ring aziridines. It is worthy to note that based on experience with nonsteroidal systems the application of electrophilic reducing agents such as diborane or lithium aluminum hydride-aluminum chloride may yet prove effective for the desired reduction. Lithium aluminum hydride accomplishes aziridine formation from the A -adducts, Le., 16 -azido-17a-iodoandrostanes (97) in a one-step reaction. The scope of this addition has been considerably enhanced by the recent... 

Iodine isocyanate, 22 1,5-Iodohydrin formation, 252 21-Iodo-3 -Hydroxypregn-5-en-20-one acetate, 208 W-iodosuccinimide, 209 Isohexylmagnesium bromide, 68... 

On storage, solutions of iodine isocyanate gradually deposit a touch-sensitive, mildly explosive solid (possibly cyanogen peroxide). 

Iodine isocyanate, from silver isocyanate and iodine, 51,... 

IODOCYCLOHEXANE, 51, 45 IODODURENE, 51, 94. trans-6-Iodoisocyandtes, general synthesis from olefins with iodine isocyanate, 51, 114... 

Silver isocyanate, with iodine to give iodine isocyanate, 51, 112... 

Iodine isocyanate, 0524 Nitrogen chloride difhroride, 3978 Nitrogen tribromide hexaammoniate, 0290 Nitrogen trichloride, 4724... 

Iodine isocyanate, 0524 Iodine(V) oxide, 4627 Iodine(VII) oxide, 4628 Iodine pentafluoride, 4355 Iodine(III) perchlorate, 4140 Iodine triacetate, 2394 Iodobenzene, 2249... 

Significant amounts of the bicyclo[3.3.1]nonane adduct and of the octahydropental-enes were isolated also from the reaction of 3 with preformed iodine acetate and iodine acetate thallium (equation 75)94 whereas only the monocyclic 1,2-adducts were obtained from treatment of 3 with iodine azide, iodine isocyanate or iodine nitrate95. The different propensity to give transannular products with these latter reagents has been related to the different positive charge density on carbons in the corresponding iodonium ion intermediates. 

Iodine isocyanate addition to olefins / 22 Halogen azide addition to olefins / 24 Via epoxides and / -mesyloxy azides / 27 By addition of alkoxyamines / 29... 

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