Sodium in propanol

The preparation of 12-oxygenated conanine derivatives and a partial synthesis of dihydroholarrhenine (4) have been reported. 3/3-Acetoxy-5a-pregnan-12,20-dione ethylene acetal (5 a), prepared from hecogenine acetate by published procedures, was transformed to the oxime (5b) which was reduced by sodium in propanol to the epimeric 20-amino-derivatives, with hydrolysis of the 3-acetoxy-group. Separation of the 20o -epimer (6a) was effected by crystallization and column chromatography. Reduction of the cathylate (6b) gave (6c) which was oxidized to the... 

The correlation of kobusine and pseudokobusine has been effected by still other routes. Dihydropseudokobusine (CCXXXV) on reduction with sodium in propanol gave dihydrokobusine (CCXXXVI). Also, reduction of either kobusine or pseudokobusine with sodium in propanol gave the same alcohol (CCXVII). 

Ursodeoxycholic acid was detected very early by Hammarsten in polar bear bile (85). It was isolated in crystalline form by Shoda (58) and characterized later by Iwasaki (84). The acid, which is the 7/3-epimer of chenodeoxycholic acid, may be prepared in good yield from 7-ketolithocholic acid by reduction with sodium in propanol according to Kanazawa et al. (86). Ursodeoxycholic acid was originally considered to be a unique constituent of bear bile but has since been detected as a minor constituent in the bile of several mammals including man (2). It is also present in human feces (52). 

The 7/3 epimer of cholic acid has been detected in the feces of man, dog, and rat (82, 119-121). It has also been found in human bile (122) and in the bile of the rat as a bacterial metabolite of cholic acid (120). The acid may be synthesized from 7-ketodeoxycholic acid by reduction with sodium in propanol (118). 

Reductive opening of the cyclopropyl ring in 9j5,19-cycloandrostan-ll-one (234) has been achieved by treatment with a large excess of sodium in iso-propanol-OD. Analysis of the product for isotopic purity after oxidation to the corresponding ketone and base-catalyzed back exchange of the 9a-deuterium [(235) (236)] shows 19% do and 10% 62 isotopic impurities. The 10% 62 product is probably due to incomplete back exchange. 

To a solution of 4 g of sodium in 200 ml of n-propanol is added 39 g of homovanillic acid-n-propyl ester (boiling point 160°C to 162°C/4 mm Hg) and the mixture is concentrated by evaporation under vacuum. After dissolving the residue in 200 ml of dimethylformamide and the addition of 0.5 gof sodium iodide, 26.2 g of chloracetic acid-N,N-diethylamide are added drop-wise with stirring at an internal temperature of 130°C, and the mixture is further heated at 130°C for three hours. From the cooled reaction mixture the precipitated salts are removed by filtering off with suction. After driving off the dimethylformamide under vacuum, the product is fractionated under vacuum, and 44.3 g of 3-methoxy-4-N,N-diethylcarbamido-methoxy phenyl acetic acid-n-propyl ester are obtained as a yellowish oil of boiling point 210°C to 212°C/0,7 mm Hg,... 

Borane and sodium in 1-propanol are good reducing agents for all three types of amides. Another reagent that reduces disubstituted amides to amines is trichloro-... 

In general, reduction of amides to alcohols is difficult. More commonly the amide is reduced to an amine. An exception uses LiH2NBH3 to give the alcohol. Reduction with sodium metal in propanol also gives the alcohol.Acyl imidazoles are also reduced to the corresponding alcohol with NaBH4 in aqueous HC1. °... 

In a 50 mL round-bottomed flask equipped with a magnetic stirrer bar were placed tert-butyl carbamate (545 mg) and n-propanol (6 mL). A solution of sodium hydroxide (183 mg) in water (12.2 mL) and tert-butyl hypochlorite (0.53 mL) were added to the solution. The resulting solution was stirred for 5 minutes and cooled to 0°C. Then a solution of DHQ2PHAL (71 mg) in n-propanol (6mL), a solution of 4-methoxystyrene in //-propanol (12.2 mL) and potassium osmate dihydrate (22.5 mg) were added sequentially to give a green solution. After 1 hour at 0 °C, the reaction mixture had turned from green to yellow. 

Japanese chemists (96) have reported the chemical conversion of kobusine into the chloramine (95). The latter was treated with sodium methoxide in methanol to afford compound 96 in which the bridged C-14-C-20 bond was cleaved. Reduction of kobusine with sodium in n-propanol, followed by acetylation afforded compound 88. Treatment of 88 with excess phenyl chloroformate in refluxing o-dichlorobenzene gave the carbamate 89. The latter was hydrogenated over Pd-C in methanol to obtain compound 90 in 94% yield. Further hydrogenation of 90 in the presence of platinum in acidic solution gave 91. Acidic hydrolysis of 91 afforded compound 92. The carbamate 92 was converted to the benzyl derivative 93 by treating with... 

Previously, LAAM has been prepared from rf-methadone (24) (Scheme 29.8) via catalytic reduction using hydrogen or, alternatively, using sodium and propanol.29 However, the most convenient method for the reduction was using sodium borohydride in the presence of cerium(III)... 

Sodium aurothiomalate is water-soluble and is given intramuscularly as an aqueous solution. Aurothioglucose is water-soluble and is given intramuscularly in either an aqueous solution or an oily suspension. Sodium aurothio-propanol sulfonate, aurotioprol, and aurothiosulfate have similar actions and uses to those of sodium aurothiomalate. They are given by intramuscular injection. 

Transannular cyclization of ketoalkenes was first reported in 1965. Treatment of the conformationally restricted ketone (104) with sodium in moist ether gave the alcohol (105 equation 127). Similarly the ketoalkene (106) transannulated in 73% yield by exposure to sodium in refluxing propanol (equation 128). Conformational restriction is not a prerequisite for transannular reaction thus the caryophyllene (107) undergoes cyclization to the alcohol (108) with lithium in liquid ammonia (equation 129). Transannulation across a nine-membered ring has also been observed upon treatment of ketone (109 equation 130) with samarium diiodide, via cyclization of the ketoalkene (110). Of more practical importance, the electrochemical transannulation of the cyclooct-4-en-l-one gives the bicyclo[3.3.0]octanol (111 equation 131). ... 

Sodium/2-propanol reduction was utilized in a stereoselective, three-step synthesis of (-)-8-phenylmcnthol12, which has found widespread use as a chiral auxiliary in organic synthesis. 

In the case of a 17-oxosteroid, 3-methoxy-14a-melhylestra-l,3.5(10)-trien-17-one. reduction with sodium/2-propanol provided the 17-alcohols in 84 6 ratio (/ /a)19. MMX calculations19 suggest a ratio of 85 15 (/ / ) at equilibrium. Thus, the single electron transfer reduction provided the more stable cyclopentanol. 

Sodium salt pentahydrate, C3H5Na02S.5H,0, crystals. Dec about 250°, So) in water methanol, ethanol. Less sol in propanol. 

Chemical Conversions of Kobusine.—Okamoto and co-workers have reported some of their recent studies of the chemistry of kobusine (74), a C-14-C-20-bridged atisine-type diterpenoid alkaloid. Since this bond constitutes a bicyclo-[3.2.1]octane system, and conversion into a double bond would violate Bredt s rule, there would appear to be no simple way to cleave it, Kobusine was reduced to (75) with sodium in n-propanol to protect the allylic alcohol. Acetylation of... 

Chromatographically pure compound 49 was reduced with sodium borohydride in propanol-2 to give, after N-acetylation, the lincosamine derivative 15 accompanied by its 7-epimer 21 in a 1.8 1 ratio. 

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