A mild and highly efficient catalytic amination procedure for chloroheteroarenes at ambient temperature using the Pd/PTABS catalytic system is reported. The protocol is selective for the amination of chloroheteroarenes using secondary amines such as piperidine, pyrrolidine, and several others. The exceptional mildness of the developed protocol is beneficial for the synthesis of a crucial Buparlisib intermediate as well as the formal synthesis of Alogliptin in competitive yields.

A mild, general, and highly efficient catalytic etherification protocol for chloroheteroarenes was developed using the Pd/PTABS catalytic system. The protocol is selective for the etherification of chloroheteroarenes using a large variety of electron-rich and electron-deficient phenol bearing synthons which include inter alia biologically and commercially important estrone, estradiol, tyrosine, and several other molecules. The mildness of the new protocol is expected to be beneficial for the synthesis of complex drugs and drug intermediates offering late-stage modification of bioactive compounds.

The thioetherification of heteroaryl chlorides is an essential synthetic methodology that provides access to bioactive drugs and agrochemicals. Due to their (actual or potential) industrial importance, the development of efficient and lowtemperature protocols for accessing these compounds is a requirement for economic and ecologic reasons. A particular highly effective catalytic protocol using the Pd/ PTABS system at only 50 °C was developed accordingly. The coupling between chloroheteroarenes and a variety of less reactive arylthiols and alkylthiols was carried out with a high efficiency. Heteroarenes of commercial relevance such as purines and pyrimidines were also found to be useful substrates for the reported transformation. The commercial drug Imuran (azathioprine) was synthesized as an example, and its preparation could be optimized. DFT studies were performed to understand the electronic effects of the tested ligands on the catalytic reaction.

2,6‐(Diphenylmethyl)‐4‐alkyl‐phenyl substituted phosphates, ArOP(O)(OH)2 (Ar=2,6‐CHPh2‐4‐R‐C6H2; R=Me (9), Et (10), iPr (11), and tBu (12)), were synthesized from the corresponding phenols. The single crystals of these compounds were obtained from their solutions of CH3CN or CH3COCH3. The molecular structures of these compounds, in the solid state, determined by single crystal X‐ray analysis reveal that they possess a hitherto unknown structural motif among monoorganophosphate esters viz., a dimeric hydrogen bonded structure involving a P−OH donor and a P=O acceptor group affording an eight‐membered ring. This structural motif is similar to what is commonly found in the solid state structures of carboxylic acids. In all of these compounds the solid state structure is restricted to the dimeric motif except in 9 where a 1D hydrogen‐bonded polymer formation is observed when it crystallized from acetonitrile. Deprotonation of these monoorganophosphates with triethylamine afforded the anionic phosphates, [ArOP(O)(OH)(O)]− containing Et3NH+ as the counter cation (Ar=2,6‐CHPh2‐4‐R‐C6H2; R=Me (13), Et (14), iPr (15), and tBu (16)). The solid state molecular structures of 13–16 again reveal hydrogen‐bonded dimeric structures in the solid state. In order to demonstrate the proof‐of‐principle with regard to the reactivity of the monoorganophosphates, we explored the reaction of 9 with ZnCl2 in the presence of pyrazole (PzH) and Et3N affording a dinuclear Zn(II) complex, [Et3NH]2[{ArOP(O)3}2{Zn(Cl)(PzH)}2] (Ar=2,6‐CHPh2‐4‐Me–C6H2) (17). The two Zn(II) centers are linked to each other by two dianionic [ArOP(O)3]2− ligands. Two additional triethylammonium cations and a terminal Zn−Cl moiety compensate the charge and complete the composition of 17.

Herein, the isolation and characterization of N-peralkyl-substituted NHC-CAAC derived triazaalkenes in three oxidation states, neutral, radical cation, and dication, are reported. Cyclic voltammetry has shown the reversible electronic coupling between the first and second oxidation to be ΔE = 0.50 V. As a proof-of-principle, to demonstrate the electron-rich nature of the triazaalkene, it was shown that it can be used as an electron donor in the reduction of an aryldiazonium salt to the corresponding arene.