Transformation of Amino Acids into Nonracemic 1-(Heteroaryl)ethanamines by the Enamino Ketone Methodology
作者:Samo Pirc、David Bevk、Amalija Golobič、Branko Stanovnik、Jurij Svete
DOI:10.1002/hlca.200690010
日期:2006.1
N-Protected L-phenylalanines 1a,b were transformed, via the corresponding Weinreb amides 2 and ethynyl ketones 3, into chiral enamino ketones 4 (Scheme 1). Similarly, L-threonine 6 was transformed in four steps into the enamino ketone 10. Cyclocondensations of 4 and 10 with pyrazolamines 11, benzenecarboximidamide (12), and hydrazine derivatives 18 afforded N-protected 1-heteroaryl-2-phenylethanamines
通过相应的Weinreb酰胺2和乙炔基酮3,将N-保护的L-苯丙氨酸1a,b转化为手性烯氨基酮4(方案1)。同样,L-苏氨酸6分四个步骤转化为烯氨基酮10。的Cyclocondensations 4和10与pyrazolamines 11,苯甲(12),和肼衍生物18得到ñ -保护的1 -杂芳基-2- phenylethanamines 15A -e,16、17和21a – k和1-杂芳基-1-氨基丙烷-2-醇23a,b具有良好的收率(方案2和3)。最后,通过催化氢化脱保护得到游离胺22a - g和24a,b(方案3)。