Primary Amine Nucleophilic Addition to Nitrilium Closo-Dodecaborate [B12H11NCCH3]−: A Simple and Effective Route to the New BNCT Drug Design

Abstract

In the present work, a convenient and straightforward approach to the preparation of borylated amidines based on the closo-dodecaborate anion [B12H11NCCH3NHR]−, R=H, Alk, Ar was developed. This method has two stages. A nitrile derivative of the general form [B12H11NCCH3]− was obtained, using a modified technique, in the first stage. On the second stage the resulting molecular system interacted with primary amines to form the target amidine products. This approach is characterised by a simple chemical apparatus, mild conditions and high yields of the final products. The mechanism of the addition of amine to the nitrile derivative of the closo-dodecaborate anion was studied, using quantum-chemical methods. The interaction between NH3 and [B12H11NCCH3]− ammonia was chosen as an example. It was found that the structure of the transition state determines the stereo-selectivity of the process. A study of the biological properties of borylated amidine sodium salts indicated that the substances had low toxicity and could accumulate in cancer cells in significant amounts.

[B10H10]2– Nanoclusters Covalently Immobilized to Hybrid SiO2 Aerogels for Slow Neutron Shielding Applications

“…First, acetonitrilium derivative is formed through electrophile-induced nucleophilic substitution . Then, the activated nitrilium group reacts with primary amine via a nucleophilic addition mechanism . This approach was successfully applied earlier for the synthesis of closo -decaborates with various substituents, including biologically active compounds .…”

“…39 Then, the activated nitrilium group reacts with primary amine via a nucleophilic addition mechanism. 53 This approach was successfully applied earlier for the synthesis of closodecaborates with various substituents, including biologically active compounds. 54 The reaction is conducted under mild conditions, providing high yield of the reaction product, which can easily be extracted from the reaction mixture.…”

New Aspects of the Synthesis of closo-Dodecaborate Nitrilium Derivatives [B12H11NCR]− (R = n-C3H7, i-C3H7, 4-C6H4CH3, 1-C10H7): Experimental and Theoretical Studies

“…In several works, nitrilium derivatives of closo-dodecaborate anions were prepared [B 12 H 11 NCR] − , R = CH 3 , CH 2 CH 3 [40,52] and different reaction protocols were applied. In paper [52], the most optimal method was established.…”

“…In several works, nitrilium derivatives of closo-dodecaborate anions were prepared [B 12 H 11 NCR] − , R = CH 3 , CH 2 CH 3 [40,52] and different reaction protocols were applied. In paper [52], the most optimal method was established. This method was based on obtaining the target substances in a glass autoclave at an oil bath temperature above 150 • C. The CF 3 COOH was used as an electrophilic inducer.…”

Non-Covalent Interactions in Organic, Organometallic, and Inorganic Supramolecular Systems Relevant for Medicine, Materials Science, and Catalysis

“…In [12], N-pyridyl ureas with 1,2, Finally, in [14], the synthesis of borylated amidines based on the closo-dodecaborate anion [B 12 H 11 NCCH 3 NHR] − (R = H, Alk, and Ar) was developed. The mechanism of the addition of amine to the nitrile derivative of the closo-dodecaborate anion was studied using DFT calculations.…”