M Iodobenzoic acid

Dehydrogenation of 3-kelo steroids. The dehydrogenation of 3-keto steroids to l,4-diene-3-ones with benzeneseleninic anhydride (8, 31) can be carried out in comparable yield by use of a process in which the benzeneseleninic anhydride is used in catalytic amounts and is continuously regenerated from diphenyl diselenide by oxidation with iodylbenzene. In practice, m-iodylbenzoic acid is a more convenient reagent, since m-iodobenzoic acid is easily recovered. 12-Keto and 12-hydroxy steroids arc oxidized by the catalytic system to A9(1 - -keto steroids in high yield. In fact, methyl desoxycholate (1) can be oxidized in this way directly to the trienedione 2 in 64% yield.1... 

Amino-5-iodobenzoic acid m-Iodobenzoic acid (45-60%, pure) CuSO added. 30... 

A cortisone synthesis using remote functionalization at an unactivated carbon centre has been achieved.97 Cortexolone (224) was converted into the 5a-H,3j3-OH derivative (formation of the bismethylenedioxy-compound followed by lithium-ammonia-ethanol reduction). Inversion98 of 3)8- to 3 -OH followed by esterification with m-iodobenzoic acid produced (225), which on irradiation in methylene chloride containing phenyl iodide dichloride gave the 9 a -chloro-derivative (not isolated). This was dehydrohalogenated and saponified by methanolic potash to yield (226) (75%) and thence, by further known steps, cortisone acetate. 

In a 3-I. beaker are placed 750 cc. of 95 per cent ethyl alcohol and 1.5 g. of finely ground copper sulfate, and the mixture is heated on a hot plate or steam bath to 70°. The diazonium slurry is added in about 30-cc. portions to the well-stirred alcohol the temperature is kept between 6o° and 70°, and the nitrogen evolution is allowed to subside considerably between additions. The final traces of diazonium slurry are washed into the alcohol with small amounts of the decanted solution, the remainder of which is then added to the alcohol in 100-cc. portions. The reaction mixture is heated and stirred at 65-70° for half an hour, and then cooled without agitation to 50. The m-iodobenzoic acid which separates is filtered with suction on a Buchner funnel, washed with three 50-cc. portions of cold water, and dried at 90-110°. There is obtained 107-116 g. of crude, brown m-iodobenzoic acid (86-93 per cent of the theoretical amount) (Note 1). 

In the channel-type structure, the dimer units are linearly stacked or helically arranged on the crystallographic two-fold axis. In the former structure, the dimer unit coincides with the repetition unit. A variety of guest molecules, such as ethanol [135], m-iodobenzoic acid [136], benzocaine [137] 25, iodine-iodide [138], 3,3-dimethylbutylamine [139], pyrene [140], trans-cinnamic acid [141], 4,7-dimethyl-... 

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