A wide range of olefins are oxidised by osmium tetroxide in aqueous alkaline solution and the OsV1" is reduced to OsVT or O S * ~ If the pH is kept in the range 8.5-1 2.5, it is possible to reoxidise the osmium compound to its initial state with oxygen at atmospheric pressure. Under these conditions osmium tetroxide acts as an oxidation catalyst. Simple alcohols, glycols, glycerol, acetone, and glucose are also oxidised under these conditions ; the products are usually oxalic acid and carbon dioxide. Styrene gives benzoic acid and carbon dioxide.

The development of a 21 -alkylation reaction which proceeds via the lithium 20(21)-enolate is described and its scope demonstrated by the preparation of a variety of 21 -alkylpregnane derivatives. Application of this process to 1 l~-acetoxy-l6a,l7a-dimethyl-5ct-pregnane-3,2O-dione (28a) and its 5P-analogue (28b) led to the corresponding 16a,l7a,21 -trimethyl derivatives. Several routes from these saturated trimethylpregnane-3,2O-diones to 1 1 P-hydroxy-l6a,17a,21 -trimethylpregna-l,4-diene-3,20-dione (Org 621 6) were explored. The best method gave Org 621 6 in 75% yield. (61 000); vmSx. 1 707 cm-l (11-ketone) (Found, M+, 592.4262. C12Hb802 requires M , 592.4280) with zinc in acetic acid.

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When fluorene is alkylated by thermal decomposition of ethyl, isopropyl, or s-butyl benzenesulphonate in a moderate excess of fluorene, substitution occurs in the nucleus at all the possible positions. The proportions of the isomeric alkylfluorenes in each alkylation product have been determined and these values compared with those obtained by other methods of alkylation.IN this work we examined the alkylation of fluorene by the thermal decomposition of ethyl, isopropyl, and s-butyl benzenesulphonate in fluorene, especially with regard to the distribution of the alkyl group in the nucleus, and we compared these results with those of other substitution reactions of fluorene. The results are summarised in the Table, together with alkylations by the alcohol or alkyl halide with aluminium chloride as catalyst. No precise figures can be given for experiments 7-10, for in these some dialkylfluorenes were also formed which could not be separated sufficiently cleanly. Alkylation of fluorene. Method

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