6 research outputs found
Simulation Of Shoreline Changes Along Muthalapozhy Harbour, India
A study of Muthalapozhy fishing harbour, located in south India, was conducted for simulating shoreline changes using LITPACK modelling tool. The analysis shows that the estimated advancement in shoreline is of the order of 45 m/year initially, which gradually reduces to 25 m/year. It was also found that the coastline advances more during the south-west monsoon (i.e. June to September) season. Simulation of breakwaters shows that the length of the breakwater should be increased by 200 m for south breakwater and 70 m for north breakwater to keep the channel operational without dredging till 2016. The results of the simulated shoreline will help the port managers for maintaining the channel round the year
Imine-palladacycles as phosphine-free precatalysts for low temperature Suzuki-Miyaura synthesis of nucleoside analogues in aqueous media
The synthesis and characterization of new water-soluble dinuclear palladacycles of the general formula [{Pd(R-C^N-SO3Na)(μ-AcO)}2] (R = H (1), OMe (2), Cl (3)) incorporating an ortho-metalated sodium 4-(N-benzylideneamino)benzenesulfonate moiety is reported. These complexes have been revealed to be excellent phosphine-free catalysts for the synthesis of functionalized nucleoside analogues involving a low-temperature Suzuki–Miyaura coupling of 5-iodo-2′-deoxyuridine with different arylboronic acids in neat water. The potential of 1–3 as synthetic precursors was also tested, and bridging acetates were cleaved by reaction with neutral PPh3, yielding the corresponding mononuclear derivatives [Pd(R-C^N-SO3Na)(AcO)(PPh3)] (R = H (4), MeO (5), Cl (6)). Analytical and spectroscopic techniques confirmed the proposed formulas and reactivities reported for complexes 1–6. Structural characterization by X-ray diffraction of single crystals grown from samples of 4 and 6 produced the unexpected but valuable crystallization-mediated compounds 4cm and 6cm that also supported the results presented here.This work has been partially supported by RTI2018-098233-B-C21 (MICINN) and
20790/PI/18 (FundaciĂłn SENECA CARM) grants. A.R.K would like to acknowledge
SERB for EMR grant (EMR/2016/005439). Professor Gregorio Sánchez, who recently
passed away, is gratefully acknowledged for his contribution to this work and his wise
and continuous advise and suppor
Quadrol-Pd(II) complexes: phosphine-free precatalysts for the room-temperature Suzuki-Miyaura synthesis of nucleoside analogues in aqueous media
Commercially available Quadrol, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine
(THPEN), has been used for the first time as N^N- donor neutral hydrophilic ligand in
the synthesis and characterization of new water soluble palladium (II) complexes
containing chloride, phthalimidate or saccharinate as co-ligands. [PdCl2(THPEN)] (1)
[Pd(phthal)2(THPEN)] (2), [Pd(sacc)2(THPEN)] (3) and the analogous complex with
the closely related N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (THEEN)
[Pd(sacc)2(THEEN)] (4) were efficiently prepared in a one-pot reaction from
[PdCl2(CH3CN)2] or Pd(OAc)2. Structural characterization of 1 and 3 by single crystal
X-ray diffraction produced the first structures reported to date of palladium complexes
with Quadrol. The resultant palladium complexes are highly soluble in water and were
found to be effective as phosphine-free catalysts for the synthesis of functionalized
nucleoside analogues under room-temperature Suzuki-Miyaura cross-coupling
conditions between 5-iodo-2'-deoxyuridine (& 5-iodo-2'-deoxycytidine) with different
aryl boronic acids in neat water. This is the first report of the coupling process
performed on nucleosides in water at room temperature.This work has been partially supported by RTI2018-098233-B-C21 (MICINN) and
20790/PI/18 (FundaciĂłn SENECA CARM) grants. A.R.K would like to acknowledge
SERB for EMR grant (EMR/2016/005439). Professor Gregorio Sánchez, who recently
passed away, is gratefully acknowledged for his contribution to this work and his wise
and continuous advice and support
Room temperature Palladium-Catalyzed C─H Functionalization of Benzothiazole with Iodo(Hetero)Arenes
A versatile synthetic protocol involving the
room temperature direct arylation of benzothiazole with a wide variety of
iodo(hetero)arenes under palladium-catalyzed conditions and promoted by HFIP as
the reaction solvent has been presented herewith. An in-situ one-pot sequential
HFIP promoted selective iodination of (hetero)arenes followed by Pd-catalyzed
direct arylation of benzothiazole has also been disclosed. Synthesis of PMX 610 (antitumor agent) analog has been disclosed and also CJM 126 (antitumor agent) has been synthesized