Ring-open azabenzonorbornadienes

Volatile aliphatic secondary amines such as diethylamine (bp 55 °C) and dimethy-lamine (bp 7°C) have been used to ring-open azabenzonorbornadienes (Scheme 10.12). To simplify the practical procedure these amines were added as their corresponding hydrogen iodide salts [17b]. 

We later found that primary and secondary amines can ring-open azabenzonorbornadienes under solventless conditions (Scheme 10.13) [ITbj. In these cases it was not necessary to include any additives to obtain high conversion and enantioselec-tivity. Both 6,7- and 5,8-disubstituted azabenzonorbornadienes could be used as substrates for this reaction, though longer reaction times were required for the 5,8- disubstituted analogues, probably due to greater steric hindrance. 

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