Kim Min Joon, Gaube Sophie M, Beh Michael H R, Smith Craig D, Thompson Alison
Department of Chemistry, Dalhousie University P. O. Box 15000 Halifax NS B3H 4R2 Canada
RSC Adv. 2019 Oct 7;9(54):31773-31780. doi: 10.1039/c9ra07527e. eCollection 2019 Oct 1.
2-Functionalised pyrroles exhibit considerable synthetic utility. Herein, the synthesis and reactivity of 2-thionoester (-C(S)OR) pyrroles is reported. 2-Thionoester pyrroles were synthesised using a Knorr-type approach from aliphatic starting materials. 2-Thionoester pyrroles were reduced to the corresponding 2-formyl pyrroles, or the deuterated formyl variant, in one step using RANEY® nickel, thereby removing the need for the much-utilised hydrolysis/decarboxylation/formylation steps that are typically required to convert Knorr-type 2-carboxylate pyrroles into 2-formyl pyrroles. 2-Thionoester pyrroles proved tolerant of typical functional group interconversions for which the parent 2-carboxylate pyrroles have become known.
2-官能化吡咯具有相当大的合成效用。本文报道了2-硫代酯（-C(S)OR）吡咯的合成及反应活性。2-硫代酯吡咯采用Knorr型方法由脂肪族起始原料合成。使用雷尼镍一步将2-硫代酯吡咯还原为相应的2-甲酰基吡咯或氘代甲酰基变体，从而无需通常将Knorr型2-羧酸酯吡咯转化为2-甲酰基吡咯所需的大量水解/脱羧/甲酰化步骤。事实证明，2-硫代酯吡咯能够耐受母体2-羧酸酯吡咯已知的典型官能团转化反应。
