Aryl Halides to Thiophenols using ThioureaJap. Pat. 63-203632, translated by 6079_Smith_W_II
(format & minor edits by metanoid)
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...I've been having a bit of trouble with this one -- the scan quality of the document is not very good in either of the versions I have, there are some complicated (to me) run-on sentences, whine whine excuses etc etc... mainly the problem is I still suck at Japanese.
Here's the meat of the patent, the experimental part... I'll tackle the rest of it in a bit, as it does look interesting.
Patent JP63203632, 1988-08-23
(Skipping summary description, theory stuff for now ...)
Example of Execution 1
181.5g 2-chloro-3-trifluoromethylpyridine and 114g thiourea were dissolved in 91g acetic acid, and reacted at 90 degrees C for 1 hour.
After the end of this reaction, and after the reaction mixture cooled, 600ml of 20% sodium hydroxide solution was thrown in; next the aqueous layer was washed with methylene chloride and afterwards the pH of the solution was adjusted to 6-7 with hydrochloric acid; the formed crystals were separated, washed, and dried, to obtain 166g 2-mercapto-3-triflouromethylpyridine (yield 92.7%). Furthermore, in this reaction process bad odors were not generated.
A reaction was performed in a similar manner to Example of Execution 1 above with the exeptions that the 91g of acetic acid was replaced with 1l of ethanol, the reaction temperature was 80 instead of 90 degrees C, and the reaction time was 26 hours instead of 1 hour. 98.9g of the target compound was obtained (yield 55%) upon completion of this halide compound and thiourea reaction. Also, in this reaction process a bad odor was generated.
Examples of Execution 2-15
These were performed in the manner of Example of Execution 1, with the raw materials used shown in the following Table 1-1, and the reaction conditions shown in Table 1-2; results are shown in Table 1-2.
Similarly with the exception of the halide substance, from for example 2-bromopyrazine, 3-bromopyridazine, 4-bromo-1-methylimidazole, 2-bromo oxazole, 5-bromo-4-nitro-isoxazole, 5-bromo-1-methyl-4-nitropyrazole, 3-bromo-1,2,4-triazole, and 2-bromotriazine, used in the reaction of Examples of Execution 1-15 above, 2-mercaptopyrazine, 3-mercaptopyridazine, 4-mercapto-1-methyl-imidazole, 2-mercapto oxazole, 5-mercapto-4-nitroisoxazole, 5-mercapto-1-methyl-4-nitropyrazole, 3-mercapto-1,2,4-triazole, and 2-mercaptotriazine would be obtained.