Dopamine D4 receptor is a G-protein coupled receptor and it is hypothesized to relate with the patho- physiology and pharmacotherapy of schizophrenia while its level in brain regions is much lower. With the help of nu- clear medicine imaging technology and suitable imaging agents

the receptors’ distribution and the level variation can be determined in living bodies. In this article we describe the synthesis of a putative dopamine D4 receptor radioli- gand

3-(4-[18F]fluorobenzyl)-8-hydroxy-1

2

3

4-tetrahydrochromeno[3

4-c] pyridin–5-one (18F-FHTP) from 4-trimethylammoniumbenzaldehyde triflate through a two-steps one-pot procedure with a total radiochemical yield of 19.7% (decay-corrected). The radiochemical synthesis of 18F-FHTP took about 105 min and its specific activity was greater than 120GBq / μmol.