Nucleophilic Reactions of Osmanaphthalynes with PMe₃ and H₂O

Abstract

Members of a new class of complexes, 2(CF 3 ), 2(H), 2(Br), 2(I), and 2(OCH 3 ), have been synthesized in a one-pot method involving the treatment of osmanaphthalynes bearing corresponding substituents (1(CF 3 ), 1(H), 1(Br), 1(I), and 1(OCH 3 )) with trimethylphosphine (PMe 3 ) and water. The main reaction process involves two steps, namely a ligandexchange with trimethylphosphine and nucleophilic addition of water to the Os�C bond of the osmanaphthalyne. The substituents have a significant influence on the rate of the reaction, as befits a nucleophilic addition. Fortunately, the key intermediate [1(OCH 3 )]' could be successfully captured, and the detailed reaction mechanism has been explored with the aid of density functional theory (DFT) calculations, which were in excellent agreement with the experimental findings. All of the target complexes have been fully characterized by 1 H, 31 P{ 1 H}, and 13 C{ 1 H} NMR spectroscopy, high-resolution mass spectrometry, and elemental analysis.

Osmaindenes: Synthesis and Reversible Mechanochromism Characteristics

“…And complexes 1 a ~6 a were prepared according to the procedures described in our published literatures. [21][22][23] Other reagents were received from commercial suppliers and used without further purification.…”

“…Target complexes 1-6 were obtained in one step from dissolved complexes 1 a-6 a in a mixed solvent of tetrahydrofuran and water (THF/H 2 O, 1 : 1, v/v) by heating under reflux for 6-13 h. Complexes 1 a-6 a are previously published by us (see Experimental Section). [21][22][23] The general synthetic route towards complexes 1-6 is shown in Scheme 1. The overall reaction involves two main processes.…”

Cancer Immunology: Immune Escape of Tumors—Expression and Regulation of HLA Class I Molecules and Its Role in Immunotherapies

“…[117][118][119][120][121] Recently, using a CRISPR/Cas9 screen to identify regulators of HLA class I, SUGT1 was found as a coregulator of MHC class I, which assists in the folding of NLRC5. 122 In addition, hypermethylation of the CpG islands within the promoter or enhancer regions of MHC class I, β 2 -m, TAP1, and TPN was found in tumor cells. Thus, the expression of MHC class I and the APM components can be directly epigenetically controlled.…”

“…This transcriptional regulation is further controlled by the expression levels of various transcription factors, such as E2F1, IRF1, NLRC5, CREB, and NF-κB 117–121. Recently, using a CRISPR/Cas9 screen to identify regulators of HLA class I, SUGT1 was found as a coregulator of MHC class I, which assists in the folding of NLRC5 122…”

Experimental and theoretical evidences for the formation of transition metal complexes with five coplanar metal–carbon σ bonds

“…As special organometallics, metallaaromatics can be defined as aromatic complexes that have one or more metal atoms in their aromatic ring [ 1–9 ]. Metallaaromatics mainly consist of metallabenzenes [ 10–16 ], metallabenzynes [ 17–20 ], heterometallaaromatics [ 21–24 ], dianion metalloles [ 25 , 26 ], spiro metalloles [ 27–29 ] and carbolong complexes [ 30 , 31 ], all containing at least one M–C σ bond. Specifically, carbolong complexes, which include metallapentalynes, metallapentalenes, and their derivatives, have not less than three M–C σ bonds.…”