6- -2-hexanone,

Use the apparatus detailed in Section 111,20. Dissolve 100 g. (123 ml.) of methyl n-butyl ketone (2-hexanone) (Section 111,152) in 750 ml. of ether and add 150 ml. of water. Introduce 69 g. of clean sodium in the form of wire (or small pieces) as rapidly as possible the reaction must be kept under control and, if necessary, the flask must be cooled in ice or in running water. When all the sodium has reacted, separate the ethereal layer, wash it with 25 ml. of dilute hydrochloric acid (1 1), then with water, dry with anhydrous potassium carbonate or with anhydrous calcium sulphate, and distil through a fractionating column. Collect the fraction of b.p. 136-138°. The yield of methyl n-butyl carbinol (2-hexanol) is 97 g. 

Dl-n-butyl-cadmium Chloroaoetyl chloride 1-Chloro-2-hexanone... 

The success of the last reaction depends upon the inertness of the ester carbonyl groups towards the organocadmium compound with its aid and the use of various ester acid chlorides, a carbon chain can be built up to any reasonable length whilst retaining a reactive functional group (the ester group) at one end of the chain. Experimental details are given for l-chloro-2-hexanone and propiophenone. The complete reaction (formation of ketones or keto-esters) can be carried out in one flask without isolation of intermediates, so that the preparation is really equivalent to one step. 

Each cross peak has x and y coordinates One coordinate corresponds to the chem real shift of a proton the other to the chemical shift to a proton to which it is coupled Because the diagonal splits the 2D spectrum m half each cross peak is duplicated on the other side of the other diagonal with the same coordinates except m reverse order This redundancy means that we really need to examine only half of the cross peaks To illustrate start with the lowest field signal (8 2 4) of 2 hexanone We assign fhis signal a friplef fo fhe protons af C 3 on fhe basis of ifs chemical shifl and fhe spin fmg evidenf m fhe ID speefrum... 

Although the ID H spectium of 2 hexanone is simple enough to be mteipieted dnectly you can see that COSY offeis one moie tool we can call on m moie complicated cases... 

A second 2D NMR method called HETCOR (heteronuclear chemical shift correlation) is a type of COSY in which the two frequency axes are the chemical shifts for different nuclei usually H and With HETCOR it is possible to relate a peak m a C spectrum to the H signal of the protons attached to that carbon As we did with COSY we 11 use 2 hexanone to illustrate the technique... 

Methyl Isoamyl Ketone. Methyl isoamyl ketone [110-12-3] (5-methyl-2-hexanone) is a colorless Hquid with a mild odor. It is produced by the condensation of acetone and isobutyraldehyde (164) in three steps which proceed via the keto-alcohol dehydration to 5-methyl-3-hexen-2-one, and hydrogenation to 5-methyl-2-hexanone. 

Hexanone Methyl n-butyl ketone 127 CsHijO p-Xylene 1,4-Dimethylbenzene 71 QHio... 

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