1 1-Bromoundecanoic acid

A 1-1., three-necked, round-bottomed flask is equipped with an internal thermometer, mechanical stirrer, dropping funnel, and calcium chloride drying tube. The flask is charged with 500 ml. of dimethyl sulfoxide and 15 g. (0.11 mole) of potassium carbonate (Note 1). The mixture is heated to 100°, and a solution of 10.0 g. (0.038 mole) of 11-bromoundecanoic acid (Note 2) in 200 ml. of dimethyl sulfoxide is added dropwise with vigorous stirring over 1... 

Bromoundecanoic acid, available from Aldrich Chemical Company, Inc., was used without further purification. 

Amplified photochemical quenching of carbazolyl fluorescence was observed in mixed LB films containing pure CUA and long chain fatty acids [12,14], A pure CUA was synthesized from 2-nitrobiphenyl and 11-bromoundecanoic acid methyl ester [12,13], Two monolayers of mixtures of CUA (fc = 0.02 to 0.50) and PA were deposited on five monolayers of cadmium arachidate at 15°C and 20 mN m 1 at pH 6.3. 

A reversed-phase HPLC post-column ion-pair extraction system was developed by Kim and Stewart [71, 72] for the analysis of carboxylic acid drugs and their salts (sodium formate, sodium acetate, 3-bromopropionic acid, 6-aminocaproic acid, 11-bromoundecanoic acid, 1-heptanesulfonic acid, / -n i t rophcny 1 acetic acid, sodium benzoate, sodium salicylate, valproic acid, probenecid, naproxen, ketoprofen, ibuprofen, mefenamic acid, flufenamic acid, and cefuroxime sodium) using a-(3,4-dimethoxy-phenyl)-4,-trimethylammoniummethylcinnamonitrile methosulfate... 

Ten grams of benzoyl peroxide is added to a solution of 370 g. (2.0 moles) of undecylenic acid in 3 1. of petroleum ether, and the mixture is held in the range of 10-20° while dry hydrogen bromide [Org. Syntheses Coll. Vol. 2, 338 (1943)] is introduced until the solution is saturated. After being cooled to —10°, the mixture is filtered to remove the crystalline precipitate, and the filtrate is concentrated under vacuum to a voliune of 500 ml. Cooling to —10° precipitates another portion of product, which is collected by filtration and combined with the first portion. Recrystallization from petroleum ether gives 350-370 g. (66-70%) of 11-bromoundecanoic acid, m.p. 49-50°. 

C11H16O3S, n-Butyl p-toluenesulfonate 67 CiiHsiBr02, 11-Bromoundecanoic acid 62... 

C11H2lBr02 11-bromoundecanoic acid 2834-05-1 459.15 39.973 2 22855 C11H2202 hexyl 2-methyl butyrate 10032-15-2 489.73 42.898 2... 

To a single-necked round-bottomed flask (250 mL) equipped with a dropping funnel and a magnetic stirrer bar, add 11-bromoundecanoic acid (21.2 g, 80 mmol). 

Bromoundecanoic acid is obtained in the presence of dibenzoyl peroxide if the HBr is prepared from bromine and tetralin but not if it is prepared from hydrogen and bromine.214... 

Bromopropyne-3-ols, 146-147 p-Bromostyrene, 571 N-Bromosuccinimide, 74-76,169 11-Bromoundecanoic acid, 479 /3-Bromo-a,/3-unsaluraled ketones, 344... 

The undecene methyl ester is saponified. The acid produced is converted to 11-bromoundecanoic acid in an anti-Markovnikov reaction under the influence of peroxides or light and hydrogen bromide. The bromoacid is converted to the ammonium salt of 11-amino undecanoic acid by ammonia and the free acid is liberated on lowering the pH. The free acid is polycondensed to polyamide (Nylon 11). 

The crystal structure of the B-form of stearic acid (von Sydow, 1955) is shown in Fig. 8.27. The molecules are arranged in an orthorhombic chainpacking structure, in bilayers. The orientation of the chain-packing subcell in relation to the methyl end group planes is Oi (101) (see Section 8.1). A modified B-form was observed in 11-bromoun-decanoic acid (Larsson, 1963a) which was termed Bi. It is isomorphous with the B-form according to X-ray diffraction data, but the OH-out-of-plane vibration in the infrared absorption spectra is different. A new form of stearic acid (Holland and Nielsen, 1963), described according to infrared absorption data, appears to be the same form as Bi in 11-bromoundecanoic acid. As the first crystal... 

Figure 8.31 The crystal structure of the D-form of 11-bromoundecanoic acid projected along the a-axis (5.63 A) (Larsson, 1963b).

---