Properties of Simple Adamantanes

Properties of Simple Adamantanes.—(+)-3-Ethyl-5-methyladamantane-l carboxylic acid, Mjig + 1.67°, has the (S) configuration (903) and (+)-l-amino-3-ethyl-5-methyladamantane the (S) configuration (904),  

The y-radiolysis of adamantane and related molecules has been reinvestigated using e.s.r. the predominant initial product is the 1-adamantyl radical. Contrary to previous beliefs, adamantanes react quickly (2 h) with neat liquid bromine at room 

Addition of diazomethane to thiodamantanone gives the spiroheterocycles (906) and (907) in differing proportions depending on the solvent cf. ref. 299). 

Burkhard, J. Jankfi, and S. Landa, Coll. Czech. Chem. Comm., 1974, 39, 1072 J. Burkhard, J. Jankfl, 

Substitutions at the 2-position of adamantane are sterically hindered, 5, 1 processes being less affected than S 2 ones. Friedel-Crafts reaction of a 2-chloroadamantane (911) with benzene gives the 2-phenyladamantane in high yield if the adamantane concentration is low (1 %). At 20% w/v concentration, intermolecular hydride transfers lead to the formation of a tertiary cation and hence the 3-phenyladamantane.  

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