One-pot two-step mechanochemical synthesis: ligand and complex preparation without isolating intermediates

Development of CN Coupling Using Mechanochemistry: Catalytic Coupling of Arylsulfonamides and Carbodiimides

“…Selectivity and stoichiometric control shown in mechanochemical reactions [4, 5] offer an opportunity for exhaustive [6] or site-selective derivatization [7] of small molecules. The recent reports [8, 9] of multistep or multicomponent syntheses of complex targets [10] suggest mechanochemistry can provide solvent-free chemistry with synthetic freedoms akin to those of solution synthesis.…”

Chapter 7. Ball-milling Mechanochemical Synthesis of Coordination Bonds: Discrete Units, Polymers and Porous Materials

“…74 (c) One-pot synthesis of the Zn(salen) complex by sequential formation of covalent bonds followed by coordination bonds and (d) analogous process conducted quantitatively in a one-pot ''all-at-once'' manner. 76 hydrogen bonding, thus demonstrating a one-pot mechanochemical process that combines three levels of molecular self-assembly (Figure 7.7b). A more complex system, involving five distinct reactants, was demonstrated by Chow et al who milled magnesium oxide, salicylic acid, 15-crown-5, acetonitrile and water all at once to obtain an acetonitrile inclusion compound of a complex salt involving a simple mononuclear metal-organic cation and a trinuclear metal-organic anion.…”

“…The consecutive reaction strategy was also applicable for the preparation of analogous complexes of nickel(II) and copper(II), by replacing zinc oxide in the second milling step with either nickel(II) acetate tetrahydrate or copper(II) acetate monohydrate, respectively. 76 A systematic exploration of multicomponent sequential and one-pot reactions based on mutually orthogonal chemical reactions was recently described by Hernández and co-workers, who targeted organometallic complexes of rhenium(I) based on the Re(CO) 3 fragment relevant for catalysis and design of model radiopharmaceuticals. 77 A judicious choice of oxidative addition and ligand exchange reactions allowed the mechanochemical one-pot synthesis of a complex organometallic fluoride complex from altogether five components, using the metal carbonyl as the simplest and most readily accessible metal precursor.…”

“…That the mechanochemical syntheses of coordination bonds and covalent bonds can be combined in a one-pot reaction was first shown by Ferguson and co-workers, who explored the synthesis of the discrete mononuclear complex of zinc with the popular bis(salicylidene)ethylenediamine (H 2 salen) ligand (Figure 7.7c,d). 76 One-pot milling of zinc oxide, salicylaldehyde and ethylenediamine quantitatively yielded the expected complex in a process that combined acid-base neutralization with the formation of covalent and coordination bonds. In addition to this three-component one-pot mechanochemical reaction, the same complex could readily be obtained by a consecutive (also known as telescopic) two-step reaction strategy in which the ligand was first mechanochemically synthesized from salicylaldehyde and ethylenediamine, followed by the addition of zinc oxide and further milling.…”

CHAPTER 6. Amino Acids and Peptides in Ball Milling

“…Organic solventfree recovery and purification have been a scarcely studied theme in fine organic chemistry, but promising methods have been published recently. 38,40,[48][49][50][51] Mechanochemical peptide syntheses would gain even more interest in the organic chemist's community if solutions addressing this challenge would emerge.…”