Toward a molecular-size tinkertoy construction set. Preparation of terminally functionalized [n]staffanes from [1.1.1]propellane

A facile but low-field synthesis of [n]staffanes (the oligomers of [1.1.1]propellane n=1-5) functionalized on one or both ends is described,and their properties are summarized. The substituents are -COOCH 3 ,-n-C 4 H 9 ,-C 6 H 5 ,-Br,-I and -SCOCH 3 , and their conversion to others,such as -COOH, -COCH 3 and -SH,is demonstrated. it is proposed that these rod-shaped molecules will be useful in the development of a molecular-size civil engeneering construction set analogous to children's toy construction sets