2-Azaadamantanes

Azaadamantanes biocide, 1, 400 mechanism, 1, 401 photoelectron spectroscopy, 2, 142 5-Azaadenines reactions, 5, 878 synthesis, 5, 901 8-Azaadenosines synthesis, 5, 895 Azaallyl cations generation, 7, 73 Aza[10]annulenes bridged... 

Stereoelectronic interaction between heteroatoms in 2-hetero-substituted 1-azaadamantanes 99PAC385. 

Using substituted 1-azaadamantanes obtained by this methodology from 1-boraadamantanes, a series of 1 1 adducts was prepared (Scheme 15 and Table 3) <1998IZV1818, 2006PAC1357>. 

Two adamantane skeletons containing a single nitrogen are possible 1-aza- (1) and 2-azaadamantane (2). Both parent compounds and their derivatives have been known for a long time. 

Some 3,5,7-trinitro-1-azaadamantane derivatives (21, 22, 23) are obtained from the corresponding 2,4,6-trinitrobenzene derivatives (24,25,26) via their... 

Azaadamantan-4,8-dione (44) is also obtained from bicyclo[3.3.1]nona-2,6-dione (45) by bromination and subsequent amination.61... 

Kirby s configurationally rigid l-azaadamantan-2-one 1 is the extreme of this class.21 23,25 The nitrogen properties of this lactam are clearly amine-like while the carbonyl is ketonic in all respects. Twisted amides undergo rapid hydrolysis or reduction and exhibit enhanced reactivity. 

The azaadamantanes with nitrogen atoms in bridgehead positions present an interesting series of compounds with 1,3-n/n interactions in a rigid cage. The PE spectrum of... 

Quinuclidine and azaadamantane Large value of 3/(ISN, 13C) of 0.6Hz in 760MR(8)438 quinuclidine, c/. that of <0.3 Hz in azaadamantane, 750MR(7)563 indicative of through space interaction in the former case. Poor agreement with INDO MO calculations ... 

Among the miscellaneous preservatives the azaadamantane derivative (25) has found a variety of uses, although it is not stable to extremes of pH or to prolonged exposures to temperatures above 50 °C. Applications of the different biocides are summarized in Table 3 other important industrial uses are reviewed elsewhere (B-66MI11501, B-68MI11504). 

These are active by a variety of mechanisms. The azaadamantane (25) decomposes in the cell to give formalin which presumably is the toxic species. The activity of 2-mercapto-benzothiazole (16) is probably related to its chelating ability (B-69MI11502), or, as already mentioned, the formation of dithiocarbamate. 

A positive charge at the coupling nitrogen induced by protonation, inductive or meso-meric effects also causes the magnitude of JCN to increase. Thus, the azaadamantane cation displays a larger JCN than the free base [135]. 

During the last years high toxicity was found for a series of bicyclic systems similar to silatranes44, S1) such as phosphatranes, azaadamantanes and trioxabicyclo (2.2.2)octanes (Table 7). This shows that the high toxicity of silatranes1 results to a considerable extent from stereochemical factors. It is connected, first of all, with... 

Treatment of the readily accessible 1-azaadamantane derivative 1 with thionyl chloride gave the mono-gem-dichloro derivative in 92% yield. Refluxing of a solution of the latter in aqueous ethanol containing triethylamine (3 eq.) gave 5-chloro-2,4,6-trimethylresorcinol in 62% yield in what has been claimed as the first example of a triple Grob fragmentation reaction. 

Azides have also been used as aminating reagent in a novel and convenient synthesis of 1-azaadamantane directly from the tetrahydrofuran complex of 1-boraada-mantane [74] (Scheme 27). 

This precedents prompted several groups to develop reaction protocols that lead exclusively to the reduced products (the reductive PKR), in order to use them in synthesis. Thus, Becker obtained diazabicyclooctanones like 208 from amines (207) as the only reaction product when they used DSAC conditions under an inert atmosphere. The nitrogen atmosphere was essential as in air they obtained mixtures of the cyclopentanones and the cyclopentenones. This group has used this methodology for the synthesis of azaadamantanes like 209 as part of the structure of certain antagonists (Scheme 59) [ 182-184], Addition of TFA to the reaction favors the formation of reduced products. A series of alkynes produced cyclopentanones as the major product when reacted with norbornene, Co2(CO)8 and TFA. The authors think TFA reacts with the cobalt complex 210, prior to the reductive elimination that gives the final product 211 (Scheme 60) [185]. 

The acidolysis of 3- Wc>-(azidomethyl)bicyclo[3.3.1]non-6-ene with methanesulfonic acid gave 4-azahomoadamant-4-ene 30 via 7t-route cyclization and rearrangement of the intermediate 2-azidoadamantane. Acidolysis of 3-mfo-azidobicyclo[3.3.1]non-6-ene, however, followed by base treatment gave 2-azaadamantan-4-ol (31)137. 

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