Oxide trinitrate, preparation

The first total synthesis of tryptoquivaline G (FTG) was achieved by Biichi et al. (158) (Scheme 15), which confirmed the proposed structure and established the relative and absolute configurations. Subsequently, Ban s group (159) effectively prepared Biichi s intermediate (90) through thallium(III) trinitrate (TTN) oxidation at a crucial step of spirolactonization. More recently, Hino s group achieved a short-step total synthesis of tryptoquivaline (160,161) and tryptoquivaline G (162) through oxidative double cyclization of the N-acyltryptophan precursor with A-iodosuccinimide (NIS) in CF3COOH (Scheme 16). 

The reactivity of nitronium salts is further enhanced in strong acid such as fluorosulfuric acid. Such solutions can be used to even trinitrate benzene to yield 1,3,5-trinitrobenzene, a reaction which was reported previously only in low yield [64-66]. 1,3,5-Trinitrobenzene is usually obtained only indirectly [67], but can be prepared in good yield by nitration of ftiete-dinitrobenzene with nitronium tetrafluoroborate in fluorosulfuric acid [68). Optimum reaction conditions require a reaction time of - 3 hr at 150 C, to yield 100% pure 1,3,5-trinitrobenzene in 50% yield [41,69]. The data in Table XX show that higher yields can be obtained at shorter reaction times, with mixtures of di- and trinitro products necessitating purification by HPLC. Longer reaction times give pure 1,3,5-trinitrobenzene but also result in oxidative losses and hence tower yield. 

Dichlorhydrin was obtained by Reboul, who also prepared ethyl propenyl ether or glycerol monethylin, C3H5(0H)20C2H5. Propenyl oxide, (C3Hg)203, was obtained, but not examined, by Berthelot and de Luca. Glyceryl trinitrate (nitroglycerine) was discovered by Sobrero. Williamson showed that it is hydrolysed by potash into glycerol and potassium nitrate, and from an... 

Regeneration of carbonyl compounds from 1,3-dithian 1-oxides can be accomplished using triethyloxonium tetrafluoroborate. Nitrosonium salts, and nitronium salts, either preformed or prepared in situ, are effective reagents for the cleavage of dithioacetals. Similarly hydrolysis of thioacetals can be performed with thallium trinitrate, and selective hydrolysis can also be achieved with this reagent [equation (59)]. ... 

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