Bromine Ritter reaction

Amantadine Amantadine, 1-adamantanamine (10.1.12), is synthesized from adaman-tane. It is directly brominated to 1-bromadamantane (10.1.10), which in Ritter reaction conditions when heated with a mixture of acetonitrile and concentrated sulfuric acid transforms into 1-acetylaminoadamantane (10.1.11). Hydrolysis of this product using alkali leads to the formation of amantadine (10.1.12) [16,17]. 

Amantadine Amantadine, 1-adamantylamine (36.1.3), is synthesized from adamantane, which is first brominated with molecular bromine to make 1-bromoadamantane (36.1.1). Interacting this with acetonitrile in a Ritter reaction conditions gives 1-acetylaminoadaman-tane (36.1.2). Hydrolysis of the last with sodium hydroxide gives amantadine [1-6]. 

Boiling compound 29 in liquid bromine for 4h also leads to formation of compound 49, but in higher yield. They were not able to add a bromine atom to the adamantane ring even when using catalysts (Lewis acids) conventionally used for difficult bromination reactions. Regardless of the reaction conditions, they could detect formation of only compound 49. They converted compound 49 to the acetoamino derivative via the Ritter reaction [45]. 

Regio- (Markovnikov) and stereo-specific (anti) incorporation of MeCN (a Ritter-type reaction) has been observed upon bromination of a series of olefins, carried out in this solvent187. The degree of this incorporation depends on the olefin structure and on the initial reagent concentrations and ratios. Thus, when performed at low initial concentrations and with the initial B /alkene ratio >2, this reaction can be used preparatively187. 

Bromination in the absence of free radical catalysts, for example, gives high yields of 1-bromoadamantane (Eq. (53)) 18s The Koch 189> and Ritter 188> 19°) reactions, which involve the initial generation of the 1-ada.-mantyl cation either by means of hydride transfer to the t-butyl cation or... 

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