The copolymerization of ethylene‒diene conjugates (butadiene (BD), isoprene (IP) and nonconjugates (5-ethylidene-2-norbornene (ENB), vinyl norbornene VNB, 4-vinylcyclohexene (VCH) and 1, 4-hexadiene (HD)), and terpolymerization of ethylene-propylene-diene conjugates (BD, IP) and nonconjugates (ENB, VNB, VCH and HD) using two traditional catalysts of C2-symmetric metallocene—silylene-bridged rac-Me2Si(2-Me-4-Ph-Ind)2ZrCl2 (complex A) and ethylene-bridged rac-Et(Ind)2ZrCl2 (complex B)—with a [Ph3C][B(C6F5)4] borate/TIBA co-catalyst, were intensively studied. Compared to that in the copolymerization of ethylene diene, the catalytic activity was more significant in E/P/diene terpolymerization. We obtained a maximum yield of both metallocene catalysts with conjugated diene between 3.00 × 106 g/molMt h and 5.00 × 106 g/molMt h. ENB had the highest deactivation impact on complex A, and HD had the most substantial deactivation effect on complex B. A 1H NMR study suggests that dienes were incorporated into the co/ter polymers’ backbone through regioselectivity. ENB and VNB, inserted by the edo double bond, left the ethylidene double bond intact, so VCH had an exo double bond. Complex A’s methyl and phenyl groups rendered it structurally stable and exhibited a dihedral angle greater than that of complex B, resulting in 1,2 isoprene insertion higher than 1, 4 isoprene that is usually incapable of polymerization coordination. High efficiency in terms of co- and ter- monomer incorporation with higher molecular weight was found for complex 1. The rate of incorporation of ethylene and propylene in the terpolymer backbone structure may also be altered by the conjugated and nonconjugated dienes. 13C-NMR, 1H-NMR, and GPC techniques were used to characterize the polymers obtained.

The mechanism of catalytic allylic C-H amination reactions promoted by Cp*Rh complexes is reported. Reaction kinetics experiments, stoichiometric studies, and DFT calculations demonstrate that allylic C-H activation to generate a Cp*Rh(π-allyl) complex is viable under mild reaction conditions. The role of external oxidant in the catalytic cycle is elucidated. Quantum mechanical calculations, stoichiometric reactions, and cyclic voltammetry experiments support an oxidatively induced reductive elimination process of the allyl fragment with an acetate ligand. Lastly, evidences supporting the amination of an allylic acetate intermediate is presented. Both nucleophilic substitution catalyzed by Ag + that behaves as a Lewis acid catalyst and an inner-sphere amination catalyzed by Cp*Rh are shown to be viable for the last step of the allylic amination reaction.

The use of small molecules as chemosensors for ion detection is rapidly gaining popularity by virtue of the advantages it offers over traditional ion sensing methods. Herein we have synthesized a series of acridine(1,8)diones (7a-7l) and explored them for their potential to act as chemosensors for the detection of various anions such as fluoride (F À ), acetate (OAc À ), bromide (Br À ), iodide (I À ), bisulfate (HSO 4 À ), chlorate (ClO 3 À ), perchlorate (ClO 4 À ), cyanide (CN À ), and thiocyanate (SCN À ). Acridinediones were found to be highly selective chemosensors for fluoride ions only. To investigate in detail the mechanism of selective fluoride ion sensing, detailed spectroscopic studies were carried out using UVvisible, fluorescence and 1 H NMR spectroscopy. Fluoride mediated (NH) proton abstraction of acridinedione was found to be responsible for the observed selective fluoride ion sensing. Quantum mechanical computational studies, using time dependent density functional theory (TDDFT) were also carried out, whereupon comparison of acridinedione interaction with fluoride and acetate ions explained the acridinedione selectivity for the detection of fluoride anions. Our results provide ample evidence and rationale for further modulation and exploration of acridinediones as non-invasive chemosensors for fluoride ion detection in a variety of sample types.An oven dried round bottom ask was charged with N-alkyl (Me/ Et) morpholine (1 g, 10 mmol, 1 equiv.) and toluene (5 mL). Subsequently, corresponding alkyl (C 5 , C 7 ) bromide (1.5 equiv.) Fig. 8 Overlay UV-vis absorption spectrum of 7i and fluoride complex 7i-F À , calculated at TD-B3LYP/6-31G(d,p).This journal is

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