Adamantyl- Ammonia

When 1-adamantyl phenyl tellurium was treated with sodium in liquid ammonia, the Te-adamantyl bond is preferentially cleaved, although the Te-phenyl bond is also attacked. The ratio of the fragmentation rates is approximately 132. 

Scheme 5 Expanding the scope of ammonia monoarylation by use of biaryl monophosphine-ligated palladacyclic pre-catalysts, i-Ad =1 -adamantyl...

Scheme 6 Ammonia monoarylation employing the k -P,N ligand Mor-DalPhos (L10 l-Ad= 1-adamantyl)...

Based on the elimination reaction, Pericas and coauthors" have developed a method for the synthesis of acetylenic ethers, derived from tertiary alcohols with a bulky alkyl group such as r -butyl and adamantyl. The key step in this synthesis is the dehydrobromination of l-bromo-2-alkoxyethylene 67 with sodium amide in ammonia or lithium diisopropylamide in a hexane-THF solution (equation 39)". ... 

Irradiation of bridgehead bromides and iodides (RX) in a variety of solvents (SH) results in the formation predominantly of the nucleophilic substitution products (RS) as well as some hydrocarbon (RH), particularly with the bromides. Both radical and heterolytic cleavage of the photoexcited RX molecules are encompassed within the mechanisms discussed. The systems studied include 1-norbornyl, 1-norbornylmethyl, and 1- and 2-adamantyl bromides and iodides. Electrochemical and metal-ammonia reduction of 1,4-dihalogenonorbornanes yields mainly nor-bornane (and not the required [2,2,l]propellane) and some l,r-bisnorbornane. ... 

The extensive work carried out by Beller in recent years has contributed to the field with a series of interesting examples, most of them based on the system palladium/di-1 -adamantyl- -butylphosphine (BuPAdj). Thus, they reported the use of ammonia as the nitrogen source for the palladium-catalyzed aminocarbonylation of aryl halides, providing a straightforward method to prepare primary amides with excellent applicability and functional group tolerance [4]. In the same group, the first carbonylative C—H activation reactions of heteroarenes to form diaryl ketones 4 were developed [5], A series of nonpreactivated heteroarenes 3 (oxazoles, thiazoles, and imidazoles) were successfully carbonylative coupled to a wide range of aryl iodides (Scheme 3.2). To avoid the formation of the noncarbonylative... 

R-4(5)-(l-adamantyl)imidazoles 1, 4, 5, were obtained by interaction of concentrated ammonia, formalin, benzaldehyde, or isobutylaldehyde with acetoxymethyl(l-adamantyl)ketone in methanol at the presence of copper acetate. 2-(l-adamantoyl)-4(5)-(l-adamantyl)imidazole (3) was obtained at the same conditions, by interaction of concentrated ammonia with acetoxymethyl(l-adamantyl)ketone without aldehyde. 2-mercapto-4(5)-(l-adamantyl)imidazole (6) was obtained by interaction of aminomethyl-(l-adamantyl)-ketone hydrobromide with ammonia thiocyanate [18] ... 

Synthesis of compound 68 by oxidative decarboxylation of adamantane carboxylic acid is described in [25], Initially, for the synthesis of 2-(l-adamantyl)benzimidazole (68), adamantan radical was obtained in sulphuric acid diluted by silver nitrate in the presence of ammonia persulfate. Then, the synthesized radical was inserted directly into the heterocycle. After N-methylation, 2-(l-adamantyl)benzimidazole (68) was transferred in l-methyl-2-(l-adamantyl)-benzimidazole (79). The experiments carried out on chicken embryo revealed high antiviral activity of both obtained compounds [25] ... 

In 1984, Tsupak and co.[64] synthesized 2-(l-adamantyl)benzimidazole (68) with 45% yield by substitution of sulpho group in benzimidazole-2-sulfonic acid with adamantly radical. The reaction was carried out in aqua acetonitrile solution. The adamantyl radical was obtained by oxidativ decarboxylation of adamantanecarboxylic acid with ammonia persulfate in silver nitrate aqua solution. 

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