Photochemical and Electrochemical Triggered Bis(hydrazone) Switch

Abstract

Herein, we report the synthesis of a double hydrazone capable of undergoing photochemical E/Z isomerization through the imine double bonds. The bis(hydrazone) 1-E,E can be considered as a "two-arm" system in which the controlled movement of each arm is obtained by photo-modulation, making possible the appearance of two isolable metastable isomeric states 1-E,Z and 1-Z,Z. Such states are characterized by very specific structural, optical, and electrochemical properties. The latter allows the reversible return from either 1-E,Z or 1-Z,Z to the 1-E,E state. Our results are of great importance in the further development of molecular machines and photochemically controlled reactions by introducing for the first time double hydrazones as tunable photochemical switches.

2‐(Hydroxyimino)aldehydes: Photo‐ and Physicochemical Properties of a Versatile Functional Group for Monomer Design

“…When HIAs bearingaprimary Rg roup (compounds 9 and 12) Figure 4. The intensitiesa re normalized to terminal -CH 3 (9-11)or-OCH 2 - (12). The intensitiesa re normalized to terminal -CH 3 (9-11)or-OCH 2 - (12).…”

“…When HIAs bearingaprimary Rg roup (compounds 9 and 12) 6 ]DMSO) for the study of the E/Z isomerismo fcompounds 9-12 and 14 after 2hphotostimulation (l = 350 nm) followed by annealinga t4 08C. The intensitiesa re normalized to terminal -CH 3 (9-11)or-OCH 2 - (12). Broken linesindicate the calculatedchemical shifts (Table 1) for different geometrical and conformationali somerso fthe HIAs.…”

“…Oximate ions are of interestf or the decontamination of toxic metal ions [10] and organophosphorus compounds. [12] and references therein). The photoinduced switch of the E/Z configurationi ni mines, oximes and hydrazones has been extensively investigated in the field of light-driven molecular machines (see Ref.…”

Multiple Reversible Dynamics of Pyrimidine Based Acylhydrazones

“…In this regard, the functional group hydrazone [4,15,20] is versatile due to its functional diversity, ease of synthesis, and its modularity. [21] Two structural characteristics that make of hydrazones attractive compounds to develop molecular machines are: the existence of a bond that can suffer E/Z isomerization sensitive to stimuli and, in many cases, the specific nature of the -NH group that allows the detection of anions and cations through H-bond interactions. [4] Herein we selected and investigated the behavior of the (Z)-N′-[phenyl(pyrimidin-2-yl)methylene]nicotinohydrazide (2) and (Z)-4-(dimethylamino)-N′-[phenyl(pyrimidin-2-yl)methylene]benzohydrazide (3), which are selectively obtained in the Z configuration by reacting phenyl(pyrimidin-2-yl)methanone with the corresponding hydrazides, nicotinohydrazide and 4-(dimethylamino)benzohydrazide, in ethanol (Scheme 1).…”

Electrochemical studies of grid and linear type M^2+ (M=Zn, Cd and Pb) complexes of a bis-(hydrazone) bearing two symmetric carboxylic groups

“…Hydrazones have become in an important type of compounds for supramolecular chemistry due to the facile synthesis, ability to coordinate metal ions and the ability of interact with UV light to undergoing configurational changes (1)(2)(3)(4)(5)(6)(7)(8) . Special attention has been paid to double hydrazones containing the framework pyridine-pyrimidine-pyridine since these compounds are able of double coordinate metal ions in a terpyridine-like manner (6,8) .…”