Synthesis of novel functionalized cispentacins through C–C oxidative cleavage of diendo-norbornene b-amino acid

Difunctionalized cispentacin derivatives with two new stereogenic centres have been synthesized from a diendo-norbornene b-amino acid in a stereocontrolled route, involving C–C double bond functionalization by dihydroxylation, followed by oxidative ring cleavage and transformation of the dialdehyde intermediates through a Wittig reactio

Asymmetric synthesis of α,β-diamino acid derivatives with an aziridine-, azetidine- and γ-lactone-skeleton via Mannich-type additions across α-chloro- N-sulfinylimines

The efficient asymmetric synthesis of new chiral γ-chloro-α,β-diamino acid derivatives via highly diastereoselective Mannich-type reactions of N-(diphenylmethylene) glycine esters across a chiral α-chloro-N-p-toluenesulfinylimine was developed. The influence of the base, LDA or LiHMDS, used for the formation of the glycine enolates, was of great importance for the anti-/syn-diastereoselectivity of the Mannich-type reaction. The γ-chloro-α,β-diamino acid derivatives proved to be excellent building blocks for ring closure towards optically pure anti- and syn-β,γ-aziridino-α-amino esters, and subsequent ring transformation into trans-3-aminoazetidine-2-carboxylic acid derivatives and α,β-diamino- γ-butyrolactones

[2,6-Bis(2-pyrimidinylthiomethyl)pyridine]dichlorocopper(II) methanol solvate

In the title compound [CuCl2(C15H13N5S2].CH3OH, the Cu2+ ion has square-pyramidal coordination geometry. The basal plane of the pyramid is formed by two Cl- ions, one pyridine N atom and one pyrimidine N atom. The fifth coordination site is occupied by the S atom of a thiomethyl group. The methanol molecule occupies an otherwise empty space in the structure

Diethyl 2,2'-[1,3-phenylenebis(methylthio)]dibenzoate

The title molecule, C26H26O4S2, assumes C2 symmetry with two C atoms and two H atoms of the central phenyl ring located on the twofold axis. The S atoms are synplanar with the benzene moiety, so the observed geometry is suitable for CS2 coordination. The o-(ethoxycarbonyl)phenylthiomethyl moiety is approximately planar and its orientation is almost perpendicular with respect to the central phenyl group

6-Oxo-6-phenyl-6-phospha-3,9-dithiabicyclo[9.4.0]pentadeca-1(11),12,14-triene

The title molecule 6-phenyl-6-phospha-3,9-dithiabicyclo [9.4.0] pentadeca-1(11), 12, 14-triene 6-oxide, C18H21OPS2, has an exodentate conformation, with the S and P atoms oriented away from the centre of the macrocyclic cavity

(Nitrato-κO)(triphenylphosphine-κP){3,6,9-trithiabicyclo[9.4.0]pentadeca-1(11),12,14-triene-κ3S3,6,9}mercury(II) nitrate hydrate hemiethanol solvate

In the title compound [Hg(NO3)(C12H16S3)-(C18H15P)][NO3].H2O.0.5C2H6O, the coordination sphere of the Hg2+ ion is a distorted trigonal bipyramid defined by the three S atoms of the trithiamacrocycle, the P atom of the triphenylphosphine group and an O atom of one nitrate group

6-Oxa-3,9-dithiabicyclo[9.4.0]pentadeca-1(11),12,14-triene

The title molecule, C12H16OS2, is partially disordered with the O and H atoms of the -CH2-O-CH2- group occupying two positions. The molecule assumes C2 symmetry and the twofold axis is located midway through the triene group and across the two partially occupied O-atom positions

Carborane-stilbene dyads: influence of substituents and cluster isomers on the photoluminescence properties

Two novel styrene-containing meta-carborane derivatives substituted at the second carbon cluster atom (Cc) with either a methyl (Me), or a phenyl (Ph) group, are introduced herein alongside with a new set of stilbene-containing ortho- (o-) and meta- (m-) carborane dyads. The latter set of compounds has been prepared from styrenecontaining carborane derivatives via Heck coupling reaction. High regioselectivity has been achieved for these compounds by using a combination of palladium complexes [Pd2(dba)3]/[Pd(t-Bu3P)2] as a catalytic system, yielding exclusively E isomers. All compounds have been fully characterized and the crystal structures of seven of them analyzed by X-ray diffraction. The absorption spectra of these compounds are similar to those of their respective fluorophore groups (styrene or stilbene), showing very low influence of the substituent (Me or Ph) linked to the second Cc atom or the cluster isomer (o- or m-). On the other hand, fluorescence spectroscopy revealed high emission intensities for Me-o-carborane derivatives, whereas their Ph-o-carborane analogues evidenced an almost total lack of fluorescence, confirming the significant role of the substituent bound to the adjacent Cc in o-carboranes. In contrast, all the m-carborane derivatives display similar photoluminescence (PL) behavior regardless of the substituent attached to the second Cc, demonstrating its small influence on the emission properties. Additionally, m-carborane derivatives are significantly more fluorescent than their o- counterparts, reaching quantum yield values as high as 30.2%. Regarding the solid state emission, only stilbene-containing Ph-o-carborane derivatives, which showed very low fluorescence in solution, exhibited a notable PL emission in films attributed to the aggregation-induced emission. DFT calculations were performed to successfully complement the photoluminescence studies, supporting the experimentally observed photophysical behavior of the styrene and stilbene-containing carborane derivatives. In conclusion, in this work is proved that it is possible to tailor the PL properties of the carborane-stilbene dyads by changing the Cc substituent and the carborane isomer.This work has been supported by Ministerio de Economía y Competitividad, MINECO, (CTQ2013-44670-R and CTQ2013-41339-P), and Generalitat de Catalunya (2014/SGR/149). Theoretical calculations have been achieved using computers from the Centro Técnico de Informática del Consejo Superior de Investigaciones Ciéntificas (CTI-CSIC). ICMAB acknowledges financial support from the MINECO, through the “Severo Ochoa” Program for Centers of Excellence in R&D (SEV- 2015-0496).Peer reviewe