Hirsch

This is extensively employed for technical purposes, and consists of an inversion of a method for the deter- 

This is specially applicable to compounds containing amino groups linked to different nuclei. The azoimides are prepared by the action of ammonia on the diazoper-bromides and, on account of the large content oi nitrogen in the former, their analysis is peculiarly well adapted for the determination of the number of diazo- 

The determination of the amino group is often conveniently accomplished by converting it into the diazoderivative and replacing the nitrogen by chlorine as a rule the diazo-compound is not isolated. The following examplewill serve to illustrate the method  

The following example will illustrate the method of working Aniline (3.1 grams) 

Abnormal chloraurates of isopropylamine, piperidine, i-methylpiperidine, 2-5-dimethylpyrrplidine and quinoline have also been described, they have the 

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Patel H M, Didymus J M, Wong K K W, Hirsch A, Skiebe A, Lamparth I and Mann S 1996 Fullerates interaction of divalent metal ions with Langmuir monolayers and multilayers in mono-substituted Cgg-malonic acid J. Chem. Soc., Chem. Commun. 611-2... 

Dietel E, Hirsch A, Zhou J and Rieker A 1998 Synthesis and electrochemical investigations of molecular architectures involving Cgg and tetraphenylporphyrin as building blocks J. Chem. See., Perkin Trans. 2 1357-64... 

Echegoyen L and Echegoyen L E 1998 Electrochemistry of fullerenes and their derivatives Accou/rfs Chem. Res. 31 593-601 HIrsch A 1994 The Chemistry of the Fuiierenes (Stuttgart Thieme)... 

HIrsch A (ed) 1999 Fuiierenes and Reiated Structures (Topics in Current Chemistry 199) (Berlin Springer)... 

When only a small quantity of solid material has to be filtered from a liquid, the small conical funnel C, usually known as a Hirsch funnel, is used in order to collect and drain the material on a very small filter-paper (see p. 68). 

The apparatus depicted in Fig. 11,34, 1, intended for advanced students, may be used for the filtration of a small quantity of crystals suspended in a solvent either a Hirsch funnel or a glass funnel with Witt filter plate is employed. The mixture of crystals and mother liquor is filtered as usual through the funnel with suction. Rotation of the three-way tap wifi allow air to enter the filter cylinder, thus permitting the mother liquor to be drawn oflF by opening the lower tap. The mother liquor can then be applied for rinsing out the residual crystals in the vessel, and the mixture is again filtered into the cylinder. When all the crystals have been transferred to the funnel and thoroughly drained, the mother liquor may be transferred to another vessel the crystals may then be washed as already described (Section 11,32). 

For the HCI salt Do exactly as above except use 6N Hydrochloric Acid. 6N HCI may be produced by diluting 60.4mL of "Muriatic Acid" to lOOmL with distilled water. Evaporate the bubbler solution to dryness then add 15ml of water, lOmL 10% NaOH soln. and heat gently to a boil with constant motion until dense white fumes appear. This will remove the Ammonium Chloride. Remove from heat while stirring as it cools down. Pulverize the dry residue, then reflux with absolute Ethanol for several minutes. Filter the refluxed soln. on a heated Buchner or Hirsch funnel, then distill the alcohol off the filtrate until crystals just begin to form. Allow the soln. to cool naturally to room temperature, then cool further in an ice bath. Filter the solution on a chilled Buchner funnel with suction. The yield of Meth iamine Hydrochloride should be around 55% of the theoretical. 

In 1890, Gabriel and Lauer (92) established that a-bromoamines react with CS2 to give 2-mercaptothiazolines (61). In the same laboratory, Hirsch (93) reacted /x-mercapto -methylthiazoline (61) with various alkyl iodides and obtained the corresponding S-alkyl derivatives. 

In 1896, Gabriel and Freiherr von Hirsch (96) condensed CSj with what they believed to be 1-aminopropylene (2-methylaziridine) and obtained isomeric 4- and S-methyl-Z-mercaptothiazoline (63 and 64). 

Hirsch, R. F. Analysis of Variance in Analytical Chemistry, Anal. Chem., 49 691A (1977). Jaffe, A. J., and H. F. Spirer, Misused Statistics—Straight Talk for Twisted Numbers, Marcel Dekker, New York, 1987. 

Characterisation of the Heavy Ends of Petroleum, API Project 60, American Petroleum Institute, 1971 J. E. Dooley, D. E. Hirsch, C. J. Thompson, and... 

A. E. Hirsch and R. J. Boyce, Dynamic Properties of EthjlenefMcrylic Elastomers M New Heat Resistant Rubber Bulletin EA-530.604, Du Pont Polymers, Stow, Ohio, May 1977. 

The reaction mixture is filtered through a Hirsch or Buchner funnel, and the bottle is rinsed with 50 ml. of benzene, which is also poured through the funnel. The filtrate is washed with two 50-ml. portions of 10% sodium chloride solution and three 2S-ml. portions of water (Note 4). The washings are extracted with three 10-ml. portions of benzene, and the combined benzene solutions are distilled under reduced pressure from a 250-ml. modified Claisen flask. The yield of ethyl -butylcyanoacetate, b.p. 108-109°/9 mm., is 79-81 g. (94-96%, based on the ethyl cyano-acetate used) (Note 5). 

Boubel, R. W., Hirsch, J. W., and Sadri, B., Particulate sampling has gone automatic. Proceedings of the 68th Annual Meeting of the Air Pollution Control Association, Pittsburgh, 1975. 

E B. Hirsch, A. Howie, R. B. Nicholson, D. W. Pashley, and M. J. Whelan. Electron Microscopy of Thin Crystals. Butterworth, Washington, 1965, Chapter 4. This sometimes incomprehensible volume is the classic textbook in the field ofTEM. 

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