Heptylate

Fig. Ill-IS. Surface tension data for aqueous alcohol illustration of the use of the Gibbs equation. (1) -butyl (2) -amyl (3) -hexyl (4) -heptyl (5) -octyl. (Data from Ref. 126).

Referring to Fig. IV-4, the angles a and /3 for a lens of isobutyl alcohol on water are 42.5° and 3°, respectively. The surface tension of water saturated with the alcohol is 24.5 dyn/cm the interfacial tension between the two liquids is 2.0 dyn/cm, and the surface tension of n-heptyl alcohol is 23.0 dyn/cm. Calculate the value of the angle 7 in the figure. Which equation, IV-6 or IV-9, represents these data better Calculate the thickness of an infinite lens of isobutyl alcohol on water. 

Calculate the limiting thickness of a lens of n-heptyl alcohol on water at 20°C. 

A further small quantity of n-heptyl alcohol may be obtained from the alkaline solution by mixing it with 50 ml. of water and distilling the distillate is saturated with salt, the oil separated, dried aad distilled from a small flask. 

Prepare a Grignard reagent from 24 -5 g. of magnesium turnings, 179 g. (157 ml.) of n-heptyl bromide (Section 111,37), and 300 ml. of di-n-butyl ether (1). Cool the solution to 0° and, with vigorous stirring, add an excess of ethylene oxide. Maintain the temperature at 0° for 1 hour after the ethylene oxide has been introduced, then allow the temperature to rise to 40° and maintain the mixture at this temperature for 1 hour. Finally heat the mixture on a water bath for 2 hours. Decompose the addition product and isolate the alcohol according to the procedure for n-hexyl alcohol (Section 111,18) the addition of benzene is unnecessary. Collect the n-nonyl alcohol at 95-100°/12 mm. The yield is 95 g. 

Also termed n-heptanoio acid, n-heptylic acid, and oaaanthio acid. 

Pelargonic acid (n-Nonoic acid), CH3(CH2),COOH. Equip a 1-litre, three-necked flask with a reflux condenser, a mercury-sealed stirrer, a dropping funnel and a thermometer. Place 23 g. of sodium, cut in small pieces, in the flask, and add 500 ml. of anhydrous n-butyl alcohol (1) in two or three portions follow the experimental details given in Section 111,152 for the preparation of a solution of sodium ethoxide. When the sodium has reacted completely, allow the solution to cool to 70-80° and add 160 g. (152 ml.) of redistilled ethyl malonate rapidly and with stirring. Heat the solution to 80-90°, and place 182 5 g. (160 ml.) of n-heptyl bromide (compare experimental details in Section 111,37) in the dropping funnel. Add the bromide slowly at first until precipitation of sodium bromide commences, and subsequently at such a rate that the n-butyl alcohol refluxes gently. Reflux the mixture until it is neutral to moist litmus (about 1 hour). 

Of the crystalline derivatives of thiols, those formed with 3 5-dinitro-benzoyl chloride are not very satisfactory since they have, in general lower melting points than those of the corresponding alcohols (compare Section 111,27,7) and do not diflfer widely from ethyl to n-heptyl. The best results are obtained with 2 4-dinitrochlorobenzene. 

One of the major contemporary chemical controversies in which I was inadvertently involved developed in the 1950s, surprisingly over the structnre of a deceptively simple seven carbon-containing bicyclic carbocation, the 2-norbornyl (bicyclo[2.2.1]heptyl) cation. The in-... 

Carbonylation of propargylic carbonates proceeds under mild neutral conditions (50 °C, I-10 atm) using Pd(OAc)2 and Ph ,P as a catalyst, yielding the 2,3-alkadienoates 18 in good yields[9,10]. The 2.3-alkadienoates isomerize to 2,4-dienoates during the reaction depending on the solvents and reaction time. 2-Decynyl methyl carbonate is converted into methyl 2-heptyl-2,3-butadienoate (19) in 82% yield. 

Ethyl (CH3CH2—) heptyl [CH3(CH2)5CH2—] and octadecyl [CH3(CH2)i6CH2—] are examples of primary alkyl groups... 

---