反应详情

By the method of Example 1, 2.99 g (3.25 mmol) of 8,20-dibenzyl-5,11,17,23-tetraisobutyl-2,4,10,14,16,22-hexamethyl-1,7,13,19-tetraoxa-4,10,16,22-tetraaza-cyclotetracosan-6,9,12,18,21,24-hexaone (1-b) (for example from Ex. 1) in 20 ml of THF were reacted with 9.75 ml (9.75 mmol) of a 1M solution of borane. Column chromatography (silica gel, Ø=4.5 cm, l=25 cm; cyclohexane:ethyl acetate 50:1 to 5:1) gave 0.72 g of tetrareduction product 8,20-dibenzyl-5,11,17,23-tetraisobutyl-2,4,10,14,16,22-hexamethyl-1,7,13,19-tetraoxa-4,10,16,22-tetraaza-cyclotetracosan-6,12,18,24-tetraon (2) (cf. Ex. 2), 0.22 g of trireduction product (1-c) and 0.91 g of unreacted starting material.