An improved synthesis of ethyl tetrahydro-1H-pyrrolizin-7a(5H)-ylacetate is reported. This valuable pharmaceutical intermediate was easily obtained from 1,7-diiodo-4-heptanone in 46% yield, thus improving the procedure reported in the literature (23% yield) which starts from 1,7-dichloro-4-heptanone. Moreover, 1,7-diiodo-4-heptanone was obtained as an easily manageable solid, in this being preferable to its 1,7-dichloro isologue, which is a quite unstable oil. The former was synthesized in high overall yield (75%) starting from the commercially available diethyl 4-oxoheptanedioate, thus overtaking the well-known problems related to the use of γ-butyrolactone.
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