Entry 1-Bromobutane

An internal reference number. Other tables in the handbook will use this number, rather than the name. 

Butane, 1-bromo. You get a systematic name and a formula. 

Dots This implies 1-bromobutane is a colorless 

The melting point of solid 1-bromobutane. Handbooks report only the TOP of the melting point range. You, however, should report the entire range. 

Density. 1.275820/4. Actually, this particular number is a specific gravity. This is a mass of the density of the liquid taken at 20 °C referred to (divided by) the density of the same mass of water at 4°C. That s what the tiny 20/4 means. Notice the units will cancel. A number without the modifying fraction is a true density (in g/ml) at the temperature given. 

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The Aldrich Catalog Entry 1-Bromobutane Entry Benzoic Acid... 

There are a few differences in the entries, what with benzoic acid being a solid, and I ll point these out. If I don t reexamine a heading, see the explanation back in the 1-Bromobutane entry for details. 

The dimethylaminomethyl group (entry 9) is easily introduced by a Mannich reaction, and lithiation occurs readily at -78°C (88JOC5685). After reaction with a variety of electrophiles, hydrolysis can be performed directly with aqueous acid to give 2-substituted imidazoles in good yield. However, the 2-lithio anion 47 was found to be quite basic, despite the base-weakening effect of coordination with the amino substituent, and thus it was capable of deprotonating the 2-butyl derivative 48 as it was formed by reaction with 1-bromobutane (Scheme 42). No such side-reac-... 

Solubility tables. Here the older editions really shine. The 43rd edition gives numerical solubility data for benzoic acid 0.18, 0.27 , 2.2 . These are the actual solubilities, in grams of benzoic acid per 100 g of water at 4, 18, and 75°C, respectively. The butyl bromide (1-bromobutane) entry has helpful solubility indicators i. insoluble in water [81, miscible in alcohol [8], miscible in diethyl ether. 

If all the chemical entries were as extensive as the one for benzoic acid, this would be the handbook of choice. Because benzoic acid has wide use in medicine and food production, and it is very important to know the physical properties of drugs and food additives, a lot of information on benzoic acid winds up in the Index. 1-Bromobutane has little such use, and the size of the entry reflects this. Unfortunately, many of the compounds you come in contact with in the organic laboratory are going to be listed with about the same amount of information you d find for 1-bromobutane, and not with the large quantities of data you d find with benzoic acid. 

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