7-Dioxo - startg

A stirred methanolic suspension of 2,3-dihydro-7-methoxy-6-methyl-5,8-dioxo-lH-pyrrolo[l,2-a]indole-9-carboxaldehyde treated under Ng with NaBH4, refluxed ca. 3 min. until a soln. is obtained, stirring continued 45 min. at room temp, under Ng, acetone added followed by a 1 iV FeGlg in 0.1 N HGl soln., dil. with water, and rapidly extracted with methylene chloride -> 2,3-dihydro-9-hydroxymethyl-7-methoxy-6-methyl-lH-pyrrolo[1,2-a] indole-5,8-dione (startg. m. f. 244). Y 80%. G. R. Allen, Jr., J. F. Poletto, and M. J. Weiss, J. Org. Ghem. 30, 2897 (1965). 

Startg. m. passed at 300°/0.01-0.05 mm through a Pyrex tube 5-(4-oxapenta-methylene)-3-morpholino-2,4-dioxo-5-azoniaimidazolidin-l-id. Y 91%. F. e. s. W. Reichen, Helv. 59, 2601 (1976) flash vacuum pyrolysis, review, s. C. Wentrup, Chimia 31, 258 (1977). 

Startg. 2-aminopyrrole, 4,4-dimethoxybutan-2-one, and coned. HCl refluxed 2 hrs. in butanol pyrrolopyridine deriv. Y 92%. F. e., also with / -dioxo compds., their diacetals, or / -oxo esters, s. A. Brodrick and D. G. Wibberly, Soc. Perkin I 1975, 1910. 

A mixture of dry Pb-tetraacetate and Ga-carbonate refluxed briefly in abs. benzene, cooled, 3,17-dioxo-19-hydroxy-Zl -androslene added, and refluxed 14 hrs. 3,17-dioxo-10j -aceloxy-zj -estrene. Y 77%. based on startg. m. consumed.—The reaction is critically influenced by the choice of the solvent and independent of steric factors. It makes available by straightforward synthesis compounds which otherwise can be obtained only by multi-step procedures. F. e. s. M. Amorosa et al., Helv. 45, 2674 (1962) without CaCOg cf. F. Alvarez, Steroids 3, 13 (1964). 

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