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Bis(acetylido) aurates(I) and thallium(I) trifluoromethylsulfonates were used to synthesize AuI–TlI metallopolymers, displaying novel and unusual structural motifs of the metal–metal backbones in the solid state: a discrete molecular cluster, 1D chains of interconnected dimers, tetramers, or dodecamers of Au–Tl units, and a 2D‐plane network, consisting of alternating edge‐linked (AuTl)6 and (AuTl)4 cycles. The formation of the different architectures was primarily controlled by the steric demand of the acetylide‐substituent groups. Thus, the bulkiest 2,6‐diisopropylphenyl derivative yielded a molecular cluster [Tl2Au3]. Most compounds showed bright visible photoluminescence with quantum yields of up to 25 % at ambient temperature. The color of the emitted light significantly differs with the network structure. Furthermore, theoretical studies of singlet excitations in the molecular cluster, as well as NMR and mass‐spectrometric investigations of the fragmentation of the metallopolymers in solution are described in detail. Bigger for better or worse: Luminescent AuI–TlI metallopolymers, displaying novel and unusual structural motifs of the metal–metal backbones in the solid state, are reported. [ABSTRACT FROM AUTHOR]

Drought stress on reproductive stages constitute a major problem for common bean (Phaseolus vulgaris L.) production because it affects flowering and pod-filling processes which are highly drought-sensitive. In this study, we used a greenhouse experiment to evaluate the response to drought stress in ten highly cultivated Brazilian genotypes in response to moderate intermittent drought during flowering and pod-filling periods (R7 and R8 stages). Morphological, biochemical, physiological and agronomic traits were used to identify tolerant cultivars and elucidate their strategies to cope this stress. The drought intensity index for the experiment reached 0.63. The cultivar IAC Imperador can be defined as a tolerant cultivar, presenting the lowest grain yield reduction (43%) and a reduced drought susceptibility index (0.65). This cultivar elevated their level of proline in roots under stress, which allowed the osmotic adjustment and the maintenance of an intermediate stomata closure during the day, which maintained the intrinsic WUE stable in NS and DS conditions. In addition, this cultivar was able to mobilize the assimilated carbon for the production of pods and grains, evidenced by the high harvest index and the high grain filling index. In this way, IAC Imperador can be used as a check in breeding programs to identify and select lineages with drought tolerance in common bean. [ABSTRACT FROM AUTHOR]

A series of neutral LM (L = [HC{(H 3 C)C(Dipp)N} 2 ], Dipp = 2,6- i Pr 2 C 6 H 3 , M = group 13: B-In, TM: Fe, Co, Ni, Cu) and L'M (L' = [HC{(CCH 2 )(CCH 3 )(DippN) 2 }], M = group 14: C-Pb) compounds including a main group 13/14 and first-row transition metal complexes were studied computationally by density functional theory (DFT). The optimised complexes were assessed in terms of structural parameters and electronic structures to find trends and characteristics that could be used to predict their reactivity towards ammonia. In addition, the differences in oxidative addition and Werner coordination complex formation depending on the identity of the central element were investigated and the Werner complexes were evaluated by QTAIM and EDA-NOCV approaches. The computational results complement the earlier experimental studies and shed light on the feasibility of isolating novel main group Werner complexes or transition metal oxidative addition products.

Intramolecular 1,2-Dipp migration of seven mesoionic carbenes (iMIC Ar ) 2 a-g (iMIC Ar =ArC{N(Dipp)} 2 CHC; Ar=aryl; Dipp=2,6-iPr 2 C 6 H 3 ) under nickel catalysis to give 1,3-imidazoles (IMD Ar ) 3 a-g (IMD Ar =ArC{N(Dipp)CHC(Dipp)N}) has been reported. The formation of 3 indicates the cleavage of an N-C Dipp bond and the subsequent formation of a C-C Dipp bond in 2, which is unprecedented in NHC chemistry. The use of 3 in accessing super-iMICs (5) (S-iMIC=ArC{N(Dipp)N(Me)C(Dipp)}C) has been shown with selenium (6), gold (7), and palladium (8) compounds. The quantification of the stereoelectronic properties reveals the superior σ-donor strength of 5 compared to that of classical NHCs. Remarkably, the percentage buried volume of 5 (%V bur =45) is the largest known amongst thus far reported iMICs. Catalytic studies show a remarkable activity of 5, which is consistent with their auspicious stereoelectronic features., (© 2020 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)