Benzoin, reaction with chloroform

Benzoin, reaction with chloroform to give 1,1,3 tnchloro n nonane, 45, 104... 

Oxidation of chalcones with TTN has been studied in detail (95, 96), and it has been shown that the products obtained depend on the amount of reagent and the solvent employed. Oxidation with 1 equivalent of TTN in methanol, methanol-chloroform, or methanol-boron trifluoride leads to acetals of the type (XXXIV) (see also Scheme 21) in yields of 20-80%. When 3 equivalents of TTN are employed, however, and aqueous glyme containing a little perchloric acid used as solvent, the products are benzils. This remarkable transformation, which proceeds in yields varying from moderate to good (40-80%), involves three distinct oxidations by TTN, and these are outlined in Scheme 22. Each individual step in this reaction sequence has been investigated in detail, with the result that useful procedures have been developed for the oxidation of both deoxybenzoins and benzoins to benzils with TTN (96). 

A solution of 0.54 g. (2 mmoles) of ferric chloride hexahydrate and 0.33 g. (3 mmoles) of diethylammonium chloride (Note 1) in 5 g. of methanol is added to a solution of 11.2 g. (0.1 mole) of 1-octene (Note 2) and 0.42 g. (2 mmoles) of benzoin (Note 3) in 36 g. (0.3 mole) of chloroform (Note 4). The resulting homogeneous mixture is introduced into a Carius tube of about 100-ml. capacity. Air is displaced by dropping a few pieces of dry ice into the tube (Note 5). The tube is sealed (Note 6), heated to 130°, kept at that temperature for 15 hours, cooled to room temperature (Note 7), and opened. The contents of the tube are transferred to a separatory fuimel, and the tube is rinsed with about 10 ml. of chloroform. The reaction mixture is washed with 40 ml. of water. The aqueous solution is extracted with 10 ml. of chloroform, and the extract is added to the original chloroform layer. Solvent is distilled at atmospheric pressure (bath temperature up to 130°). The distillation flask is allowed to cool, and distillation is continued at 25 mm. (bath temperature up to 120°) (Note 8). The flask is cooled again, and distillation is continued to dryness at 0.1 mm. (bath temperature up tc 150°), giving crude l,l,3-trichloro- -nonane (19.4 g.) as a yellow oil, b.p. 60-85° (0.1 mm.), 1.4650. The purity of this... 

Spec A = 665 nm of the titanium-methylene blue-ascorbic acid redox reaction Spec A= 420 nm of the yellow Tiron derivative (pH = 5.2 to 5.6) Spectrophotometric determination of tungsten with thiocyanate after both tungsten(VI) and molybdenum(VI) are extracted into chloroform as benzoin a-oxime complexes... 

Properties Wh. scales, needles, crystals, benzoin odor sol. in alcohol, ether, chloroform, benzene, carbon disulfide si. sol. in water m.w. 122.13 dens. 1.2659 m.p. 121.25 C b.p. 249.2 C subl. at 100 C flash pt. 121.1 C Toxicology LD50 (oral, rat) 2530 mg/kg, (IP, mouse) 1460 mg/kg mod. toxic by ingestion, IP routes poison by subcut. route severe eye/skin irritant may cause human intolerance reaction, asthma, hyperactivity in children TSCA listed Precaution Combustible when exposed to heat or flame reactive with oxidizing materials... 

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