Angela De Munno

1,3-Dithiane polymers for the supported synthesis of ketones

Abstract The synthesis of polymeric reagents containing an odourless propane-1,3-dithiol functionality is reported. Their usefulness for the solid phase synthesis of ketones via the umpoled alkylation of 1,3-dithianes is demonstrated.

Unexpected behavior of the methoxymethoxy group in the metalation/formylation reactions of 3-methoxymethoxyanisole

The formation of tetrasubstituted benzenes and doubly lithiated intermediates in metalation/formylation reactions of 3-methoxymethoxyanisole has been observed with the methoxymethoxy group acting as a leaving group in some cases.

Vinyl monomers containing 1,2-thia-, selena- and tellurazole systems, their polymers and copolymers

Synthese de ces monomeres, homopolymerisation radicalaire et copolymerisation avec le styrene

New synthesis of 1,2,5-selenadiazoles

Synthese par reaction de thiadiazole-1,2,5 ou de derives monosubstitues avec un reactif de Grignard puis le melange SeCl 4 /Se (correspondant a SeCl)

Synthesis of Model Molecules and NMR Analysis of Polymeric Reagents Based on Propane‐1,3‐dithiol and 1,3‐Dithiane Systems

Purposely synthesized model compounds, one- and two-dimensional NMR spectra and simulations are used for a full 1H and 13C NMR spectroscopic investigation of soluble copolymeric reagents for supported organic syntheses containing (1,3-propanediyl)bis(benzenesulfonate), (1,3-propanediyl)bis(thioacetate), propane-1,3-dithiol, and 1,3-dithiane functions. The collected NMR spectroscopic data confirm the possibility of rapid and accurate assessments of preparations and applications of the newly prepared copolymeric reagents, without resorting to special equipment.

77Se-1He spin-spin coupling constants in PMR spectra of 1,2,5-selenadiazole and its 3-methyl derivative

Abstract PMR spectra of 1, 2, 5-selenadiazole and its 3-methyl derivative have been obtained. Observed values of long range couplings between 77 Se and ring protons together with other features of the spectra such as chemical shifts and J 13 C− 1 H are discussed and correlated with selenophene and 1, 2, 5-thiadiazole PMR data.

C-alkylation of nitriles : a useful route to 2-ethoxyalkyl derivatives of cadaverine planned for enzyme study

Abstract The cadaverine derivatives 1–4 containing ethoxyalkyl groups of variable length in position 2, planned as model molecules for the diamine oxidase active site study, were prepared and characterized exploiting as key precursors both 5-(N,N-dimethylamino)pentanonitrile or ethyl 2-cyano-5-(N,N-dimethylamino)pentanoate.

Vinyl derivatives of heterocyclic systems and their polymers: isoxazole derivatives

3,5-Dimethyl-4-vinylisoxazole (3) has been prepared from pentane-2,4-dione by way of 1-(3,5-dimethylisoxazol-4-yl)ethanol (2) by two different methods, one of which gives an overall yield greater than 75%. Compound (3), in the presence of radical initiators, is transformed into polymers with pendant isoxazole rings.

Conformation studies by nuclear magnetic resonance spectroscopy in liquid crystal solvents. An investigation of torsional angles, reorientation, and order matrices in 3-, 4-, and 5-phenylisoxazole

The n.m.r. spectra of 3-(1), 4-(2), and 5-phenylisoxazole (3) partially oriented in the nematic phase of a liquid crystalline solvent have been studied. A twisted conformation around the bond connecting the two rings is preferred, with a twist angle of ca. 18° for compounds (1) and (3) and ca. 20° for compound (2). Reorientation of these molecules is correlated with the internal rotation, while the direction of the principal order axis, with respect to a reference axis system fixed on the phenyl ring, depends on molecular shape.

Conformation studies by nuclear magnetic resonance spectroscopy in nematic phases: 3-phenyl-1,2,5-oxa-, -thia-, and -selena-diazole

The 100 MHz n.m.r. spectra of 3-phenyl-1,2,5-oxa-(1), -thia-(2), and -selena-diazole (3) partially oriented in the nematic phase have been obtained and analysed. The spectral analysis affords examples of conformational situation in molecules containing two aromatic rings of six and five members respectively. A preferred twisted conformation around the bond between the two rings has been found, the twisting angle θ ranging from 18 to 21°. The conformation is little influenced by the heteroatom in position 2 and by the solvent. The results are discussed in connection with theoretical EHT calculations.