73638-56-9Relevant academic research and scientific papers
Copper-mediated nucleophilic radiobromination of aryl boron precursors: Convenient preparation of a radiobrominated PARP-1 inhibitor
Zhou, Dong,Chu, Wenhua,Voller, Thomas,Katzenellenbogen, John A.
supporting information, p. 1963 - 1967 (2018/04/23)
The copper-mediated nucleophilic radiobromination of aryl boron precursors with a radiobromide ion is a novel radiolabeling method that is efficient and robust. High radiochemical conversion (RCC) was observed using a variety of solvents, temperatures and catalysts. The reaction is also clean and is feasible for purification to obtain high chemical and radiochemical purity. This method provides a very useful route for the preparation of radiobrominated pharmaceuticals, including a radiobromine labeled PARP-1 inhibitor, and it is a valuable addition to the family of copper-mediated radiolabeling processes.
No-carrier-added Radiobromination and Radioiodination of Aromatic Rings using In Situ Generated Peracetic Acid
Moerlein, Stephen M.,Beyer, Werner,Stoecklin, Gerhard
, p. 779 - 786 (2007/10/02)
Peracetic acid generated in situ from aqueous hydrogen peroxide and glacial acetic acid was examined as an oxidizing agent for electrophilic aromatic bromination and iodination without chlorinated side products.No-carrier-added (n.c.a.) 77Br and 131I were used with simple organic aromatic compounds or aryltrimethyl-tin, -germanium, and -silicon organometallic compounds to identify reaction parameters which influence this electrophilic halogenation method.N.c.a. aromatic halogenodeprotonation using peracetic acid was relatively slow and resulted in high labelling yields only with aromatic rings that were activated toward electrophilic substitution.By contrast, high radiochemical yields were rapidly obtained via iododestannylation of aromatic rings regardless of their degree of electronic activation.Useful labelling yields were also achieved using bromodestannylation reactions with aromatic rings deactivated toward electrophiles, but optimum yields with activated systems required the use of germylated arenes as substrates.The practical aspects of aromatic halogenodemetallation and halogenodeprotonation as n.c.a. electrophilic halogenation techniques with in situ generated peracetic acid are outlined.
Regiospecific No-Carrier-Added Radiobromination and Radioiodination of Arylmethyl Group IVb Organometallics
Moerlein, Stephen M.,Coenen, Heinz H.
, p. 1941 - 1948 (2007/10/02)
A series of para-substituted aryltrimethyl-silicon, -germanium, and -tin compounds were treated at room temperature with no-carrier-added (n.c.a.) 77Br and 131I to compare their utility as substrates for regiospecific aromatic halogenation.Dichloramine-T was used as an in situ oxidant in acidic, polar, or non-polar reaction solvents.N.c.a. aromatic halodemetallation was regiospecific for all substrates, radiochemical yields were generally higher for 131I than 77Br, and halogenation yields increased as Si Ge Sn.Arguments are presented for a substitution mechanism involving a ?-complex intermediate with bond formation as the yield-determinig step.Although high yields were obtained for the n.c.a. aromatic halogenodestannylations irrespective of aromatic substituent or solvent, significant chlorination occured as a side-reaction.N.c.a. aromatic halogenodegermylation produced high radiochemical yields with insignificant chlorination, but the radiohalogenation yields were sensitive to ring deactivation and solvent effects.N.c.a. aromatic halogenodesilylation gave high yields only in activated aromatic systems.The relative benefits of each demetallation reaction for regiospecific n.c.a. radiolabelling or preparative halogenation of aromatic rings are outlined.
