Succinimide with triphenylphosphine

The Beckmann rearrangement of ketoximes with triphenylphosphine and iV-chloro-succinimide occurs at room temperature almost instantaneously and their corresponding secondary amides are obtained in high yields (equation 83). The triphenylphosphine 271 is activated by the iV-chlorosuccinimide 270 affording the salt 272, which is attacked by the iV-hydroxy group of the oxime 217 forming the intermediate 273. 

OH — X. Pi. carbohydrate hydroxyl group can be replaced by halogen (bromine, chlorine, iodine) by treatment in DMF with 2 eq. each of triphenylphosphine and an N-halosuccinimidc. The by-products are succinimide and triphenylphosphine oxide. Yields are generally high. Primary hydroxyl groups can be selectively replaced in the presence of secondary hydroxyl groups. 

Thio ethers. The reagent reacts with primary and secondary alcohols at 20° in the presence of tri- -butylphosphine (triphenylphosphine is not so effective) to form phenyl thioethers, tri-n-butylphosphine oxide, and succinimide. The reaction proceeds with inversion. It is limited to N-(aryIthio)succinimides, since N-(alkyIthio)succinimides are desulfurized by phosphines. 

The synthesis of a gas-generating composition starts with the synthesis of a poly(vinyltriazole). A substituted triazole salt is added to a free radical brominating reagent, such as A-bromo succinimide, and to a radical initiator to form a brominated triazole. The brominated triazole is then added to triphenylphosphine to form a Wittig salt. Formaldehyde in alkaline medium effects the formation of a vinyltriazole salt, which can be polymerized with AIBN and a catalytic amount of a cationic initiator or a Ziegler-Natta catalyst. The reaction sequence is shown in Figure 9.10. 

The reaction of 204 with succinimide, triphenylphosphine, and diethyl azodicarboxylate (Et02CN=NC02Et) gave (after chromatography) a 20% yield of the diastereomer of 204 with inverted alcohol stereochemistry. Provide a mechanistic explanation for this observation. (Gephyrotoxin- 3)... 

N-Phenylmaleimide and triphenylphosphine in glacial acetic acid stirred 1 hr. on a steam bath N-phenyltriphenylphosphoranylidenesuccinimide (Y 66%) dissolved in methanol, and treated with a slight excess of pyridine-4-carboxalde-hyde N-phenyl-(4-pyridylidene)succinimide (Y 83%). F. e. s. E. Hedaya and S. Theodoropulos, Tetrahedron 24, 2241 (1968). 

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