Novel Carbazole (Cbz)-Based Carboxylated Functional Monomers: Design,Synthesis, and Characterization

A series of novel functional carbazole (Cbz)-based carboxylated monomers were synthesized and characterized. A Clauson-Kaas procedure, a deprotection step, amide coupling, and hydrolysis were utilized as key chemical reactions towards the multistep synthesis of monomers in good to excellent isolated yields. The design strategy was further extended to complex carbazole-COOH monomers incorporated arylazo groups as photoreactive moieties. In addition, photoreactive hybrid carbazole (Cbz)-pyrrole (Pyr)-based carboxylated monomers, comprising a pyrrole core linking a carbazole and a photoreactive phenylazide or benzophenone moiety through an amide spacer in the molecular structure, were also synthesized. The latter can be utilized for surface modification of polymeric films in their monomeric form or as polymeric microparticles (MPs).     

The particular sensitivity of silyl ethers of D-glucal toward two Vilsmeier-Haack reagents POCl3.DMF and (CF3SO2)2O.DMF. Their unique and selective conversion to the corresponding C(6)-O-formates.

The two electrophilic Vilsmeier-Haack reagents POCl3.DMF 2 or (CF3SO2)2O.DMF 3 mediate the one-step and selective conversion of O-triethylsilyl (O-TES), O-tert-butyldimethylsilyl (O-TBDMS), O-tert-butyldiphenylsilyl (O-TBDPS), and O-triisopropylsilyl (O-TIPS) ethers of D-glucal to the corresponding C(6)-O-formates.     

Study of structural and electronic transport properties of Ce-doped LaMnO3

The structural and electronic transport properties of La_1−x Ce _x MnO₃ (x=0.0–1.0) have been studied. All the samples exhibit orthorhombic crystal symmetry and the unit cell volume decreases with Ce doping. They also make a metal-insulator transition (MIT) and transition temperature increases with increase in Ce concentration up to 50% doping. The system La_0.5Ce_0.5MnO₃ also exhibits MIT instead of charge-ordered state as observed in the hole doped systems of the same composition.     

CC bond formation using allylic organozirconium compounds. Nucleophilic additions on to isolated and in situ generated η-pentadienyl-Fe(CO)3/Fe(CO)2PPh3(+1) cations

Two nucleophilic allylic organozirconium compounds 9-10 (R⁵: Me and tBu) have been reacted with acyclic isolated η⁵-pentadienyl-Fe(CO)₃/Fe(CO)₂PPh₃(+1) cations or with these intermediates generated in situ (Uemura-like conditions). Depending on reaction conditions, iron-complexed η⁴-dienyl-Fe(CO)₃/Fe(CO)₂PPh₃ and σ,η³-π-allyl-Fe(CO)₃/Fe(CO)₂PPh₃ condensation products have been selectively isolated and fully characterized.     

Two connected inverse spectral transforms

We establish a transformation which connects the potentials of the one-dimensional Dirac and Klein-Gordon operators. This transformation links the solutions of the nonlinear evolution equations solvable by means of the two inverse spectral transforms which use the Dirac and Klein-Gordon direct and inverse spectral problems.