scholarly journals Koordinationschemie ambivalenter Liganden, VIII1 Synthese und Reaktivität ionischer und kovalenter Sulfinato-Komplexe von Tetraorganyl-VB-Elementen des Typs R4'EO2SR / Coordination Chemistry of Ambivalent Ligands, VIII1 Synthesis and Reactivity of Ionic and Covalent Sulfinato Complexes of Tetraorganyl-VB-Elements of the Type R4'EO2SR

1978 ◽  
Vol 33 (1) ◽  
pp. 47-58 ◽  
Author(s):  
Ingo-Peter Lorenz ◽  
John Koshy Thekumparampil

Abstract The synthesis of the sulfinato derivatives 1-7 of pentavalent VB-elements follows equation (2). These compounds differ significantly in their physical and chemical properties and in their structures. In between the extremes of the purely ionic tetramethylam-monium sulfinates la-c and the typically covalent and pentacoordinated tetraorganyl-sulfinato-O-stiboranes 6-7, there are the hexa-or pentavalent compounds of phosphorus and arsenic 2 and 4 or 3 and 5 with sulfinato-O,O' or sulftnato-O linkage, which dissociate readily into their ionic components. 1 a-c are suitable for the synthesis of sulfones according to equation (3). All of the methylsulfinato derivatives can be easily transformed (equation (4)) into the corresponding sulfonates by air oxidation. Only the tetraphenylsulfinato-O-stiboranes 7 a-c show SO2-elimination forming pentaorganylstiboranes (equation (5)). IR, mass and in some cases NMR spectra are reported.

1981 ◽  
Vol 36 (11) ◽  
pp. 1444-1450 ◽  
Author(s):  
Max Schmidt ◽  
Erich Sametschek

Abstract The first examples of the hitherto unknown 1,2,4-Trithia-3,5-diborolanes with B-O-C-bonds have been synthesized and characterised. The diiodo substituted ring (2) reacts with 2,6-dimethylphenol, to form 3,5-bis-(2,6-dimethylphenyloxi)-1,2,4-trithia-3,5-di-borolane (3) and HI. 3,5-Diethoxi-1,2,4-trithia-3,5-diborolane, 5, and C2H5I are formed via the cleavage of diethylether by 2. From 2 and diisopropylether, the corresponding 3,5-diisopropyloxi-1,2,4-trithia-3,5-diborolane (6) is formed. The unsymmetrical ethers methyl-t-butylether and methylphenylether undergo reactions with 2 resulting in the formation of 3,5-dimethyloxi-1,2,4-trithia-3,5-diborolane (8) (besides t-C4H9I) and 3,5-diphenyloxi-1,2,4-trithia-3,5-diborolane (10) (besides CH3I). The thermal stability of the new compounds is increasing with increasing size of R in the -OR group and from aliphatic to aromatic R in this group. IR, Raman, 1H NMR and 11B NMR spectra of the compounds are reported as well as some physical and chemical properties.


2021 ◽  
Author(s):  
Runzhi Sun ◽  
Xiuqing Song ◽  
Fan Xie ◽  
Huiqin Wang ◽  
Hong Yan

Abstract The structural symmetry is of great significance on the unique physical and chemical properties that closely related to pharmacological applications. To investigate the effects of structural symmetry on the NMR spectra, C2-3,9-diazatetraasteranes and non-C2-3,9-diazatetraasteranes were selected as the research object. They were synthesized by the self-dimerization and cross-dimerization of diethyl 1,4-dihydropyridine-3,5-dicarboxylates, respectively. The differences and similarities in NMR spectra of these two types of 3,9-diazatetraasteranes were discussed by the 1D-NMR and 2D-NMR analysis. The single-crystal X-ray diffraction (XRD) was used to demonstrate directly their structural symmetry.


1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.


2017 ◽  
pp. 31-43
Author(s):  
Berta Ratilla ◽  
Loreme Cagande ◽  
Othello Capuno

Organic farming is one of the management strategies that improve productivity of marginal uplands. The study aimed to: (1) evaluate effects of various organic-based fertilizers on the growth and yield of corn; (2) determine the appropriate combination for optimum yield; and (3) assess changes on the soil physical and chemical properties. Experiment was laid out in Randomized Complete Block Design, with 3 replications and 7 treatments, namely; T0=(0-0-0); T1=1t ha-1 Evans + 45-30-30kg N, P2O5, K2O ha-1; T2=t ha-1 Wellgrow + 45-30-30kg N, P2O5, K2O ha-1; T3=15t ha-1 chicken dung; T4=10t ha-1 chicken dung + 45-30-30kg N, P2O5, K2O ha-1; T5=15t ha-1 Vermicast; and T6=10t ha-1 Vermicast + 45-30-30kg N, P2O5, K2O ha-1. Application of organic-based fertilizers with or without inorganic fertilizers promoted growth of corn than the control. But due to high infestation of corn silk beetle(Monolepta bifasciata Horns), its grain yield was greatly affected. In the second cropping, except for Evans, any of these fertilizers applied alone or combined with 45-30-30kg N, P2O5, K2O ha-1 appeared appropriate in increasing corn earyield. Soil physical and chemical properties changed with addition of organic fertilizers. While bulk density decreased irrespective of treatments, pH, total N, available P and exchangeable K generally increased more with chicken dung application.


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