1.3.3- trimethyl-6-azabicyclo octane

Heating 3,4-bis(phenylsulfonyl)furoxan with a solution of sodium butoxide in butanol followed by reduction with trimethyl phosphite gives furazan 281 (Scheme 183). Compound 281 was converted into dialkoxy derivative 282 with the lithium salt of ( )-l-azabicyclo[2.2.2]octan-3-ol in 33% overall yield (96W012711, 97EUP773021, 98JMC379). 

In order to maximize yields and regioselectivity in the Friedlander synthesis of quinolines, the bicyclic pyrrolidine base l,3,3-trimethyl-6-azabicyclo[3.2.1]octane (TABO) was utilized to good effect. TTie reaction was carried out with unactivated methyl ketones <03JOC467>. The ratios of the two products were 86% 2-substituted and 14% 2,3-disubstituted. 

While most reducing agents lead to the expected bornylamines as products of the reduction of camphor oxime (see above), diisobutylaluminum hydride is a notable exception, as a ring-enlarged amine, (1/ ,47 )-1.8,8-trimethyl-2-azabicyclo[3.2.1]octane (67) is obtained in high yield when starting with the oxime of (+ )-camphor16, It has been used as the lithium salt in enantioselective deprotonation and elimination reactions (Section C.). 

Another interesting point is the low coproduction of impurities. Nevertheless we observed the formation of small amounts of low boiling points products (Xi.Xj) compared with IPDA. After analytical characterisation we assigned to the most important of them the azabicyclic (1,3,3-trimethyl-6-azabicyclo[3,2,1]octane) structure. In anhydrous conditions as in our case, byproduction of aminoalcohol is minimized. On the other hand, when water is present the proportion of aminoalcohol increases. These observations can be explained by the following mechanism. 

Lawson and co-workers have described the preparation and use of hydrocarbon-soluble lithium amides such as the N-lithio salts of l,3,3-trimethyl-6-azabicyclo[3.2.1]octane (21) and hexamethyleneimine (22). The initiator 21 was soluble when prepared by metalation of the bicyclic amine with n-butyllithium in hexanes. Initiator 21 in the presence of 0.27 equivalents ofTMEDA was used to polymerize an 80/20 (wt/wt) blend of butadiene and styrene at 50 °C in hexanes.After conventional termination and work-up, the resulting polymer exhibited a good correspondence between calculated (Aln= 100 X lO gmoP ) and observed (Aln = 99.7 x 10 gmol ) molecular weights, a relatively broad molecular weight distribution (Al /Aln = 1 82), and 52% 1,2-microstructure (Tg= -42 °C) with little (0.7%) block styrene. 

Ring expansion. A soln. of camphor-3-glyoxylic acid in 10%-NaOH treated with 10%-NaNO2 then with 10%-HGl l,8,8-trimethyl-3-hydroxy-3-azabicyclo[3.2.1]-octan-2-one-exo-4-carboxylic acid. Y 55%. F. e. s. L. D. Hatfield and W. D. Huntsman, J. Org. Ghem. 32, 1800 (1967). 

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