An Efficient Synthetic Approach to Calix[n]furan[4-n]pyrroles and the Calix[n]tetrahydrofuran[4-n]pyrrolidines

作者：Maupillier William; Journot Guillaume; Stoeckli Evans Helen; Neier Reinhard^*

来源：European Journal of Organic Chemistry, 2017, 2017(40): 6023-6037.

DOI：10.1002/ejoc.201701156

• Calixarenes
• Synthetic methods
• Hydrogenation
• Macrocycles
• Conformation

A scalable synthesis of calix[n]furan[4-n]pyrroles and their fully reduced analogues, calix[n]tetrahydrofuran[4-n]pyrrolidines obtained by hydrogenation of their aromatic relatives, was developed and optimized. The hydrogenation reaction was studied at several selected pressures (P = 100, 50 and 15 bars) and high diastereoselectivity was observed for the four possible calix[n]tetrahydrofuran[4-n]pyrrolidines. Moreover, two of the saturated macrocycles were obtained with good overall yields starting from easily accessible calix[4]furan. The conformation of the eight macrocycles was analyzed by X-ray diffraction and although a classical 1,3-alternate conformation of this type of compound was observed for the aromatic macrocycles, two distinct types of conformation were observed with the calix[n]tetrahydrofuran[4-n]pyrrolidines.

• 出版日期2017-11-2