37010-56-3Relevant academic research and scientific papers
Direct Experimental Evidence for Halogen–Aryl π Interactions in Solution from Molecular Torsion Balances
Sun, Han,Horatscheck, André,Martos, Vera,Bartetzko, Max,Uhrig, Ulrike,Lentz, Dieter,Schmieder, Peter,Nazaré, Marc
supporting information, p. 6454 - 6458 (2017/05/29)
We dissected halogen–aryl π interactions experimentally using a bicyclic N-arylimide based molecular torsion balances system, which is based on the influence of the non-bonded interaction on the equilibria between folded and unfolded states. Through comparison of balances modulated by higher halogens with fluorine balances, we determined the magnitude of the halogen–aryl π interactions in our unimolecular systems to be larger than ?5.0 kJ mol?1, which is comparable with the magnitude estimated in the biomolecular systems. Our study provides direct experimental evidence of halogen–aryl π interactions in solution, which until now have only been revealed in the solid state and evaluated theoretically by quantum-mechanical calculations.
Unusual regio- and stereo-selectivity in Diels-Alder reactions between bulky N-phenylmaleimides and anthracene derivatives
Chen, Hao,Yao, Erdong,Xu, Chi,Meng, Xiao,Ma, Yuguo
, p. 5102 - 5107 (2014/07/08)
Unusual regio- and stereo-selectivity in Diels-Alder (D-A) reactions were achieved between bulky N-phenylmaleimides and anthracene derivatives. Using multiple substituents with steric hindrance on both diene and dienophile, a noticeable shift toward 1,4-addition was successfully obtained. The substrate scope in this reaction was broad and the highest yield of anti-1,4-adducts was over 90%. Novel structures of anti-1,4-adducts were confirmed by single crystal X-ray diffraction analysis. This study not only provides the first reported method of synthesizing anti-1,4-adducts and achieving otherwise unattainable regio- and stereo-selectivity, but also elucidates the importance of combining the steric effects of two reactants to shift products toward 1,4-adducts. Moreover, the resulting 1,4-adducts could be further functionalized through their halogen groups via carbon-carbon coupling reactions.
