Acetone 1,3-diacetoxy

Behandelt man 9a-Brom-17a-hydroxy-1 l( ,21-diacetoxy-3,20-dioxo-pregnadien-(1,4) mit Chrom(II)-chlorid in Aceton, so wird als einziges Reaktionsprodukt 17a.-Hydr-oxy-1 lp,21-diacetoxy-3,20-dioxo-5,9-cyclo-pregnen-(l) (36% d.Th. F 186-191°) er-halten6 ... 

The 3,12-diacetoxy-wor-cholanic acid may be purified by crystallization from acetone. It melts at 207-208°. 

The crude carbinol is acetylated and dehydrated by refluxing its solution in 1 1. of glacial acetic acid and 500 ml. of acetic anhydride for 1 hour. The solution is then concentrated to about 500 ml. by distillation. After cooling overnight, the crystalline 3,12-diacetoxy-5A or-cholanyldiphenylethylene is collected on a filter and washed with acetic acid. The yield is 95-105 g. (63.5-70.0%) of material melting at 154-157° (Note 5). This product is sufficiently pure to be used for the preparation of Mor-desoxycholic acid (p. 38) one crystallization from acetone gives white crystals which melt at 156-157.5° fully purified material melts at 159.5-160.5°. 

N.CH[.CH2.C(N02)2. (CH2)2. COOHfc, CnHlsNs014 mw441.31 N l5.87% OBto C02 —56.20% fine white tabular or plate crysts mp 154° (decompn) d 1.631g/cc. V sol in acetone si sol in heptane and toluene hydrolyzed by water. Prepn is in six steps. The first step is the reaction of 1,3-diacetoxy-2-nitfopropane with Na methyl-4,4-dinitrobutyrate to yield... 

A solution of 2a,3a,16a,17a-diepoxy-17p-acetoxy-5a-androstane (25 grams), prepared from 3,17-diacetoxy-5a-androstane-2,16-diene (Chem. Abs. 1960, 54, 8908) by treatment with m-chlor-perbenzoic acid, in piperidine (120 ml) and water (40 ml) was boiled under reflux for 5 days, the solution was concentrated and the product precipitated by the addition of water. The solid was collected, dissolved in dilute hydrochloric acid, filtered to give a clear solution and precipitated by the addition of sodium hydroxide solution. Crystallization from acetone gave 2p,16p-bis-piperidino-5a-androstan-3a-ol-17-one (18.9 grams), MP 179-185°C. 

B. trans, trans-, A-Diacetoxy-, 3-butadiene. The diacetate above (83.0 g., 0.373 mole), dimethyl acetylenedicarboxylate2 (54.0 g., 0.380 mole), and benzene (250 ml.) are placed in a 500-ml. flask and boiled under reflux for 6 hours (Note 7). The solution is filtered to remove the remaining mercury and mercuric salts, and the benzene is distilled under reduced pressure. The residual viscous yellow oil is distilled under reduced pressure (Note 8). A mixture of l,4-diacetoxy-l,3-butadiene and dimethyl phthalate is collected at 140-155° (18-20 mm.), bath temperature 170-200°, from which the diene crystallizes as colorless needles in the cooled receiver. The solid in the receiver is broken up and washed onto a Buchner funnel with petroleum ether (b.p. 60-70°). The solid is then pressed between sheets of filter paper to remove excess dimethyl phthalate and recrystallized from acetone-petroleum ether (b.p. 60-70°) (ca. 1 2) (Note 9). The yield of colorless needles of trans,trans- 1,4-diacetoxy-1,3-butadiene, m.p. 102-104°, is 26-31 g. (41-49%) (Notes 10, 11, and 12). 

Eine Hydrierung der C=C-Doppelbind ung zu e,ndo-6,exo- 7 - und exo-6,e,xo-7-Diacetozy-3-oxa-tricyclo[3.2.t.02 ]octan (VI und VII, S. 684) tritt in alien untersuchten Losungsmitteln auf. Das endo-endo-Isomere IX, bildet sich auBcrdcm in Ather oder Cyclohexan. Aceton wird in Form eines 2-Oxo-propyl-Restes inkorporiert (Substanz X). In Acetonitril tritt zus tzlich Isomerisierung zu l,o-Diacetoxy-3-oxa-tetracydo[3.3.0.02 9.Ol 6]octan (VIII) ein. 

Also obtained by reaction of 3,4-diacetoxy-a-iodo-acetophenone with cyclohexylamine in the presence of potassium carbonate in boiling acetone for 4 h (24%) [4796]. 

The reaction of trans- or m-3,4-diacetoxy-3,4-dihydro-2ff-pyran derivatives with acetyl acetone or 8-ketoesters afforded a mixture of trans- and cw-2-substituted 5-acetoxy-5,6-dihydro-2//-pyran derivatives (eq 93). ... 

---