Synthetic Hydrophilic Porphyrins. Preparations and Spectra of Alkoxycarbonylmethyl and Carboxymethyl Pyridinium Porphyrins

1989 ◽  
Vol 42 (12) ◽  
pp. 2265 ◽  
Author(s):  
DP Arnold

The preparation and spectroscopic properties of a quaternary pyridinium porphyrin containing ethoxycarbonylmethyl groups are described. Partial saponification of the ester groups yields a series of mixed ester/carboxylate salts which show evidence of strong intermolecular association in aqueous solution. The fully saponified tetracarboxylate inner salt was prepared in high yield and has properties which conflict with a previous report.

2020 ◽  
Vol 17 (8) ◽  
pp. 628-630
Author(s):  
Vu Binh Duong ◽  
Pham Van Hien ◽  
Tran Thai Ngoc ◽  
Phan Dinh Chau ◽  
Tran Khac Vu

A simple and practical method for the synthesis on a large scale of altretamine (1), a wellknown antitumor drug, has been successfully developed. The synthesis method involves the conversion of cyanuric chloride (2) into altretamine (1) by dimethylamination of 2 with an aqueous solution of 40% dimethylamine and potassium hydroxide in 1, -dioxan 4in one step to give altretamine (1) in high yield.


2009 ◽  
Vol 87 (1) ◽  
pp. 110-120 ◽  
Author(s):  
Julia R Khusnutdinova ◽  
Peter Y Zavalij ◽  
Andrei N Vedernikov

Oxidation of phenyl PtII complexes K[(dpms)PtIIPh2], 1, (dpms)PtIIPh(MeOH), 2, (dpms)PtIIPh(OH2), 3, and methyl PtII complex (dpms)PtIIMe(NH2Ph), 6, with O2 in aqueous or methanol solutions under ambient conditions leads to corresponding (dpms)PtIVR(X)OH complexes (R = X = Ph, 7; R = Ph, X = OH, 8; R = Ph, X = OMe, 9; R = Me, X = NHPh; 11; dpms = di(2-pyridyl)methanesulfonate). Complexes 7–9 could be isolated in high yield. Complex 11 as well as its phenyl analogue (dpms)PtIVPh(NHPh)OH, 10 can be prepared in high yield by oxidation of corresponding (dpms)PtIIR(NH2Ph) with H2O2 in methanol. Phenyl PtII complexes (dpms)PtIIPh(HX) derived from HX = aniline and DMSO, 4 and 5, respectively, are inert toward O2. The rate of oxidation of 1–5 with O2 decreases in the order 1 > 3 ~ 2 » 4, and 5 is unreactive. Methyl analogues are significantly more reactive compared with their phenyl counterparts. Proposed mechanism of oxidation with O2 includes formation of anionic species (dpms)PtIIR(X)– responsible for reaction with dioxygen. Attempts at C–O and C–N reductive elimination from phenyl PtIV complexes 7–10 do not lead to phenyl derivatives PhX at 80–100 °C, consistent with the results of the DFT estimates of corresponding activation barriers, ΔG0 exceeding 28 kcal/mol.Key words: platinum phenyl complexes, oxidation, dioxygen, aqueous solution, mechanism.


2007 ◽  
Vol 544-545 ◽  
pp. 901-904 ◽  
Author(s):  
Ji Bum Yang ◽  
Tae Gyung Ko ◽  
Sang Jin Jung ◽  
Jae Hee Oh

We report on a process in which CuO nanopowder was produced in a high yield by adopting ultrasonic in aqueous solution. In our experiment, CuCl2 solution was reacted with NaOH solution and NaNO2, at ambient conditions applying ultrasonic for 5 min. Precipitation was performed by varying the molar ratios of NaOH/CuCl2 and NaNO2/CuCl2. CuO nanoparticles of ~ 5 nm and spherical shape were obtained at the NaOH/CuCl2 of 2.0 and the NaNO2/CuCl2 of 0.097. Without ultrasonication, an amorphous phase was formed at these conditions. This indicates that sonochemical reaction facilitates direct formation of the nanosized CuO particles. In addition, the particle morphology varied from sphere through ellipsoid to needle forms depending on pH. In thick films prepared with the CuO powder for gas sensing, the maximum CO gas sensitivity reached 93 % at the temperature of 250 °C and depended linearly on CO concentration in log scale over the range of 10 ~ 104 ppm.


2019 ◽  
Vol 20 (21) ◽  
pp. 5512 ◽  
Author(s):  
Lili Du ◽  
Zhiping Yan ◽  
Xueqin Bai ◽  
Runhui Liang ◽  
David Lee Phillips

Nitrenium ions are common reactive intermediates with high activities towards some biological nucleophiles. In this paper, we employed femtosecond transient absorption (fs-TA) and nanosecond transient absorption (ns-TA) as well as nanosecond time-resolved resonance Raman (ns-TR3) spectroscopy and density function theory (DFT) calculations to study the spectroscopic properties of the N(4,4′–dibromodiphenylamino)–2,4,6–trimethylpyridinium BF4− salt (1) in an acidic aqueous solution. Efficient cleavage of the N–N bond (4 ps) to form the N,N–di(4–bromophenyl)nitrenium ion (DN) was also observed in the acidic aqueous solution. As a result, the dication intermediate 4 appears more likely to be produced after abstracting a proton for the nitrenium ion DN in the acid solution first, followed by an electron abstraction to form the radical cation intermediate 3. These new and more extensive time-resolved spectroscopic data will be useful to help to develop an improved understanding of the identity, nature, and properties of nitrenium ions involved in reactions under acidic aqueous conditions.


1979 ◽  
Vol 18 (12) ◽  
pp. 3417-3422 ◽  
Author(s):  
Raffaele P. Bonomo ◽  
Rosario Cali ◽  
Francesco Riggi ◽  
Enrico Rizzarelli ◽  
Silvio Sammartano ◽  
...  

1983 ◽  
Vol 38 (1) ◽  
pp. 30-33
Author(s):  
W. Petz ◽  
S. Kremer

Fe2(CO)9 reacts with Cl2C(COOEt)2 to give the paramagnetic complex Fe[ClC(COOEt)2]3 in high yield. The magnetic and spectroscopic properties of this complex are discussed.


1987 ◽  
Vol 42 (9) ◽  
pp. 1088-1096 ◽  
Author(s):  
Hubert Schmidbaur ◽  
Cornelia Dörzbach

Preparative methods have been explored for the synthesis of small, volatile polysilaalkanes, which could serve as starting materials for the production of amorphous silicon a-SiC:H. High yield pathways have been developed for H3SiCH2CH2SiH3 and H3SiCH2CH2CH2SiH3. These compounds can be converted into symmetrically halogen-functional derivatives through the reac­tions with SnCl4 or Br2. The homologous H3SiCH2CH2SiH2CH3 has also been prepared and halogenated, starting from the corresponding vinylsilane via the hydrosilylation route. Allylsilanes were the source of the synthesis of H3SiCH2CH=CH2, CH3SiH2CH2CH=CH, SiH2(CH2CH = CH2)2, SiH2(CH2CH2CH2SiH3)2, or HSi(CH2CH2CH2SiH3)3. Methylated deriva­tives are also available. - Some physical and spectroscopic properties of the new compounds have been investigated. In particular. NMR data were collected and used for an assessment of structure and isomerism.


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