In high performance perovskite based solar cells, CH3NH3PbI3 is the key material. We carried out a study on charge diffusion in spin-coated CH3NH3PbI3 perovskite thin film by transient fluorescent spectroscopy. A thickness-dependent fluorescent lifetime was found. By coating the film with an electron or hole transfer layer, [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) or 2,2',7,7'-tetrakis...

In the present study, we describe the photochemical behaviour of 2-mesyloxy phenyl ketones 8 and 12 bearing a cyclopropane moiety in the side-chain. Irradiation of 8 and 12 leads to the corresponding benzoyl spiro[2.2]pentanes as a consequence of an initial gamma-H-shift, subsequent elimination of MsOH (accompanied by a spin-center shift) and cyclization of the resulting 1,3-diradicals. In cont...

The title compound, C18H12Br2O6, was synthesized from Morita-Baylis-Hillman adducts. It incorporates the bromin-ated spiro-hexa-dienone moiety typically exhibited by compounds of this class that exhibit biological activity. Both the brominated cyclo-hexa-dienone and the central five-membered rings are nearly planar (r.m.s. deviations of 0.044 and 0.016 Å, respectively), being almost perpendicul...

The first organocatalytic Michael-cyclization cascade reaction between isothiocyanato oxindoles and unsaturated pyrazolones has been developed. The multicyclic spiro[oxindole/thiobutyrolactam/pyrazolone] core structures containing three contiguous stereogenic centers, including two spiro quaternary centers, were prepared with excellent diastereo- (up to >20 : 1) and enantioselectivities (up to ...

We report an unusual face selective reduction of the exocyclic double bond in the α-methylene-γ-butyrolactone motif of spiro-oxindole systems. The spiro-oxindoles were assembled by an indium metal mediated Barbier-type reaction followed by an acid catalyzed lactonization.

A general and direct strategy for the synthesis of chiral spiro-aziridine oxindoles has been developed via an aza-Corey-Chaykovsky reaction of isatin-derived N-tert-butanesulfinyl ketimines with excellent selectivity (dr = 98:2 to >99:1). The method is explored for the synthesis of chiral 3-substituted spiro-aziridine oxindoles with high (2S,3S)-selectivity over (2S,3R).

let $r$ be a reversible ring which is $alpha$-compatible for an endomorphism $alpha$ of $r$ and $f(x)=a_0+a_1x+cdots+a_nx^n$ be a nonzero skew polynomial in $r[x;alpha]$. it is proved that if there exists a nonzero skew polynomial $g(x)=b_0+b_1x+cdots+b_mx^m$ in $r[x;alpha]$ such that $g(x)f(x)=c$ is a constant in $r$, then $b_0a_0=c$ and there exist nonzero elements $a$ and $r$ in $r$ such tha...

we observe some new characterizations of $n$-presented modules. using the concepts of $(n,0)$-injectivity and $(n,0)$-flatness of modules, we also present some characterizations of right $n$-coherent rings, right $n$-hereditary rings, and right $n$-regular rings.

in this paper, we introduce the concept of the   generalized aip-rings as a generalization of the generalized quasi-   baer rings   and generalized p.p.-rings. we show that the class of the generalized aip-rings is closed under direct products and morita invariance. we also characterize the 2-by-2 formal upper triangular matrix rings of this new class of rings. finally, we provide sever...