1-Azabicyclo undecanes synthesis

Azabicyclo[2.1.0]pentane-3-carboxylic acid antimicrobial activity, 7, 346 l-Azabicyclo[3.3.3]undecane — see Manxine 1 - Aza-2-boracyclohexane, 1 -methyl-synthesis, 1, 647... 

Leonard and Goode used the hydrogenation of hydroxyimino diesters of the structure I over Copper-Chromium oxide at 250°C and 36 MPa H2 for the synthesis of 1-azabicyclo compounds of the structure II (Scheme 8.8).76 By this method pyrrolizid-ine (Ila), octahydropyrrocoline (lid), quinolizidine (lib), l-azabicyclo[5.3.0]decane (lie), l-azabicyclo[5.4.0]undecane (Ilf) (eq. 8.38), and l-azabicyclo[5.5.0]dodecane (lie) were prepared in 50-60% yields. However, attempts to prepare bicyclic amines... 

This account follows the same scheme as last year s. Synthesis is discussed in sections according to reaction type and is followed by a brief consideration of miscellaneous reactions. The emphasis on synthetic studies continues but the increasing interest in the pharmacology of many of the novel systems is not discussed. Recent topics include the analgesic activity of l-azabicyclo[4,4,l]-undecanes, 3-azabicyclo[3,2,l]octanes, 3-azabicyclo[3,2,2]nonanes, 9-azabicyclo[3,3,l]nonanes, and substituted quinuclidines. ... 

A convenient synthesis of pyrrolizidines, indolizidines, quinolizidines, and l-azabicyclo[5.4.0]undecanes has been described. The synthesis proceeds from the appropriate cyclic a-amino-acid ester by alkylation with a suitably substituted malonic ester. The procedure for quinolizidines is illustrated in Scheme 98. 

Acid chlorides of a-tertiaryamino acids are unstable, being thermally decarbonyl-ated to iminium salts, which yield secondary amines and aldehydes when treated with water.If the iminium salt is suitably placed for cyclization e.g. as in (278), this readily occurs and l-azabicyclo[5,4,0]undecane (279) was obtained in 77% yield. The potential for this reaction is considerable the authors have also applied it to a tetrahydroberberine synthesis (Scheme 125) the product was obtained in 79% in a reaction time of 2.5 minutes ... 

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