Au(III) complexes with tetradentate-cyclam-based ligands

• Ann Christin Reiersølmoen,
• Thomas N. Solvi and
• Anne Fiksdahl

Beilstein J. Org. Chem. 2021, 17, 186–192, doi:10.3762/bjoc.17.18

• chiral mono-Boc-1,2-diamines and (dialkyl)malonyl dichloride via open diamide-bis(N-Boc-amino) intermediates (65–91%). Deprotection and ring closure with a second malonyl unit afforded the cyclam tetraamide precursors (80–95%). The new protocol allowed the preparation of the target cyclam derivatives (53

• –59%) by a final optimized hydride reduction. Both the open tetraamine intermediates and the cyclam derivatives successfully coordinated with AuCl3 to give moderate to excellent yields (50–96%) of the corresponding novel tetra-coordinated N,N,N,N-Au(III) complexes with alternating five- and six

• ; cyclam derivatives; cyclopropanation; Introduction The importance of gold for humankind dates long back, and gold is linked to the evolution of many parts of the society. Contrary to the general fascination and importance of gold, the potential as homogenous catalyst has been neglected, compared to a

A direct method for the N-tetraalkylation of azamacrocycles

• Andrew J. Counsell,
• Angus T. Jones,
• Matthew H. Todd and
• Peter J. Rutledge

Beilstein J. Org. Chem. 2016, 12, 2457–2461, doi:10.3762/bjoc.12.239

• , as part of ongoing efforts to develop multi-functionalised cyclam derivatives for fluorescence sensing [25][26][27][28][40][41] and other biomedical applications [14][15][16][42][43]. However, we found the previously reported methods to be at best capricious when it comes to substitution with

Efficient deprotection of F-BODIPY derivatives: removal of BF₂ using Brønsted acids

• Mingfeng Yu,
• Joseph K.-H. Wong,
• Cyril Tang,
• Peter Turner,
• Matthew H. Todd and
• Peter J. Rutledge

Beilstein J. Org. Chem. 2015, 11, 37–41, doi:10.3762/bjoc.11.6

• using two common Brønsted acids: treatment with trifluoroacetic acid (TFA) or methanolic hydrogen chloride (HCl) at room temperature followed by work-up with Ambersep® 900 resin (hydroxide form) achieves this conversion in near-quantitative yields. We have an ongoing interest in triazolyl-cyclam

• derivatives incorporating fluorescent dyes for sensing applications [22][23][24][25]. Looking to extend these systems to incorporate an F-BODIPY motif, we have synthesized the Boc-protected triazolyl-cyclam/F-BODIPY derivatives 3 and 4 from 2,4-dimethyl-1H-pyrrole (5), 4-nitrobenzaldehyde (6, Scheme 2A) and 4