1078574-77-2Relevant academic research and scientific papers
Metal-Free Multicomponent Tandem Polymerizations of Alkynes, Amines, and Formaldehyde toward Structure- and Sequence-Controlled Luminescent Polyheterocycles
Wei, Bo,Li, Weizhang,Zhao, Zujin,Qin, Anjun,Hu, Rongrong,Tang, Ben Zhong
, p. 5075 - 5084 (2017)
Sequence-controlled polymers, including biopolymers such as DNA, RNA, and proteins, have attracted much attention recently because of their sequence-dependent functionalities. The development of an efficient synthetic approach for non-natural sequence-controlled polymers is hence of great importance. Multicomponent polymerizations (MCPs) as a powerful and popular synthetic approach for functional polymers with great structural diversity have been demonstrated to be a promising tool for the synthesis of sequence-controlled polymers. In this work, we developed a facile metal-free one-pot multicomponent tandem polymerization (MCTP) of activated internal alkynes, aromatic diamines, and formaldehyde to successfully synthesize structural-regulated and sequence-controlled polyheterocycles with high molecular weights (up to 69800 g/mol) in high yields (up to 99%). Through such MCTP, polymers with the in situ generated multisubstituted tetrahydropyrimidines or dihydropyrrolones in the backbone and inherent luminescence can be easily obtained with high atom economy and environmental benefit, which is inaccessible by other synthetic approaches.
New hyperpolarized contrast agents for 13C-MRI from para-hydrogenation of oligooxyethylenic alkynes
Reineri, Francesca,Viale, Alessandra,Giovenzana, Giovanbattista,Santelia, Daniela,Dastru, Walter,Gobetto, Roberto,Aime, Silvio
experimental part, p. 15047 - 15053 (2009/03/12)
Two alkyne derivatives, which contain one and two oligooxyethylenic chains respectively, showed to be good substrates for para-hydrogenation reactions, yielding the corresponding hyperpolarized alkenes in good yields. A suitable theory has been developed to account for the observed results, fully explaining the different para-H2 induced effects observed upon the para-hydrogenation of symmetrically and asymmetrically substituted alkynes in ALTADENA and PASADENA modes. The oligooxyethylenic substituent provides good water solubility to the para-hydrogenated symmetrical derivative. 13C-MR in vitro images of the latter derivative were obtained both in acetone and in water solutions (130 mM), using the ALTADENA procedure and after application of the field cycling procedure which allows acquisition of an in-phase 13C carbonyl resonance. The finding that the hydrogenated product is water-soluble in contrast to the parent alkyne which is not allows for the pursuit of a fast phase-transfer separation from the organic solvent, the unreacted substrate, and the catalyst to obtain a ready-to-use water solution suitable for further in vivo MRI applications.
