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Use of B-sp³-alkyl reagents for Suzuki-Miyaura couplings under aqueous micellar catalysis conditions is reported. Studies as to substrate scope, use in a four-step one-pot sequence, and reaction medium recycling exemplify the synthetic utility of this technology. OBBD (B-alkyl-9-oxa-10-borabicyclo[3.3.2]decane) derivatives are easily made and utilized for couplings under mild conditions. Comparisons were also made between OBBD and 9-BBN (B-alkyl-9-borabicyclo[3.3.1]nonane) derivatives as reaction partners. [ABSTRACT FROM AUTHOR]

An especially mild, safe, efficient, and environmentally responsible reduction of aromatic and heteroaromatic nitro-group-containing educts is reported that utilizes very inexpensive carbonyl iron powder (CIP), a highly active commercial grade of iron powder. These reductions are conducted in the presence of nanomicelles composed of TPGS-750-M in water, a recyclable aqueous micellar reaction medium. This new technology also shows broad scope and scalability and presents opportunities for multistep one-pot sequences involving this reducing agent. [ABSTRACT FROM AUTHOR]

The impact of varying percentages of an organic solvent added to reactions run in aqueous nanomicelles as the reaction medium has been investigated. Issues such as rates of reaction, percent conversion, and yield, as well as various practical aspects (e.g., effect on stirring, etc.), are discussed, leading to an operationally simple method for the general improvement of potentially problematic systems across a broad range of reaction types, in particular for reactions run at scale. [ABSTRACT FROM AUTHOR]

Electronic and photophysical characterization is presented for a series of bis-heteroleptic [Ru(bpy)2(R-CAQN)]+ complexes where CAQN is a bidentate N-(carboxyaryl)amidoquinolate ligand and the aryl substituent R = p-tolyl, p-fluorobenzene, p-trifluoromethylbenzene, 3,5-bis(trifluoromethyl)benzene, or 4-methoxy-2,3,5,6-tetrafluorobenzene. Characterized by a strong noninnocent Ru(dπ)-CAQN(π) bonding interaction, density functional theory (DFT) analysis is used to estimate the contribution of both atomic Ru(dπ) and ligand CAQN(π) manifolds to the frontier molecular orbitals of these complexes. UV-vis absorption and emission studies are presented where the noninnocent Ru(dπ)-CAQN(π) bonding scheme plays a major role in defining complex electronic and photophysical properties. Oxidation potentials are tuned over a range of 0.92 V with respect to the [Ru(bpy)3]2+ reference system, hereafter referred to as 12+, by varying the degree of R-CAQN fluorination while maintaining consistently strong and panchromatic visible absorption properties. Electron paramagnetic resonance (EPR) spectroscopy is employed to experimentally map delocalization of the unpaired electron/electron-hole within the delocalized Ru(dπ)-CAQN(π) singly occupied valence molecular orbital of the one-electron oxidized complexes. EPR data is complemented experimentally by UV-vis-NIR spectroelectrochemistry, and computationally by molecular orbital Mulliken contributions and spin-density analysis. It is ultimately demonstrated that the CAQN ligand framework provides a simple yet broad synthetic platform in the design of redox-active transition metal chromophores with a range of electronic and spectroscopic characteristics hinting at the diversity and potential of these complexes toward photochemical and catalytic applications. [ABSTRACT FROM AUTHOR]

The production of cells capable of carrying multiple transgenes to Mb-size genomic loci has multiple applications in biomedicine and biotechnology. In order to achieve this goal, three key steps are required: (i) cloning of large genomic segments; (ii) insertion of multiple DNA blocks at a precise location and (iii) the capability to eliminate the assembled region from cells. In this study, we designed the iterative integration system (IIS) that utilizes recombinases Cre, ΦC31 and ΦBT1, and combined it with a human artificial chromosome (HAC) possessing a regulated kinetochore (alphoid tetO -HAC). We have demonstrated that the IIS-alphoid tetO -HAC system is a valuable genetic tool by reassembling a functional gene from multiple segments on the HAC. IIS-alphoid tetO -HAC has several notable advantages over other artificial chromosome-based systems. This includes the potential to assemble an unlimited number of genomic DNA segments; a DNA assembly process that leaves only a small insertion (<60 bp) scar between adjacent DNA, allowing genes reassembled from segments to be spliced correctly; a marker exchange system that also changes cell color, and counter-selection markers at each DNA insertion step, simplifying selection of correct clones; and presence of an error proofing mechanism to remove cells with misincorporated DNA segments, which improves the integrity of assembly. In addition, the IIS-alphoid tetO -HAC carrying a locus of interest is removable, offering the unique possibility to revert the cell line to its pretransformed state and compare the phenotypes of human cells with and without a functional copy of a gene(s). Thus, IIS-alphoid tetO -HAC allows investigation of complex biomedical pathways, gene(s) regulation, and has the potential to engineer synthetic chromosomes with a predetermined set of genes.