3- 2-Phenyl-l,3-dithian-2-yl indole

Stirring is continued for 2 hours at room temperature, and then methanol is added until a clear solution is obtained (ca. 10 ml. of methanol is required, and some heat is generated). When the solution has cooled, it is washed successively with 200 ml. of aqueous 2N potassium carbonate and 200 ml. of water. The aqueous phases are combined, washed with three 100-ml. portions of chloroform, and discarded. The organic phases are then combined, dried over sodium sulfate, and decolorized with activated carbon. Concentration of the chloroform solution thus obtained provides three crops of pale yellow crystals, which are washed with 30% hexane in chloroform and dried for 2 hours at 80°/0.1 mm. The total yield of 3-(2-phenyl-l,3-dithian-2-yl)indole is 22.3-25.4 g. (72-81%), m.p. 167-169° (Note 7). This material requires no further purification for use in Parts D or E. 

L//-Indole, 3<2-phenyl-l, 3-dithian-2-yl), 10 Indoles, 34 Indoles, 3-acyl-, 8 Indoles, 3 -alkyl, 8 Isocyanate, chlorosulfonyl [Sulfuryl chlonde isocyanate], 41 Isocyanate,2-propyl- [Propane, 2-iso-cyanato-], 96... 

C. 3-(2-Phenyl-l,S-dithian-2-yl)indole [IH-Indole, 3-(2-phenyl-l,S- dithian-2-yiy. A solution of 24.2 g. (0.10 mole) of 2-methylthio-2-phenyl-l,3-dithiane and 6.86 g. (0.050 mole) of indole [li/-Indole] in 600 ml. of chloroform is placed in a 2-1., three-necked hask fitted with a mechanical stirrer and a 100-ml., pressure-equalizing dropping funnel. The reaction mixture is stirred vigorously, and a solution of 25 ml. (about 0.2 mole) of boron trifluoride etherate [Borane, trifluoro, compd. with l,T-oxybis[ethane](l 1)] (Note 6) in 50 ml. of chloroform is added over 10 minutes. An orange-brown, resinous precipitate forms as the slightly exothermic reaction proceeds. After a further 10 minutes of stirring, a solution of 5.86 g. (0.050 mole) of indole in 60 ml. of chloroform is added in one portion. 

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