Keywords:Epoxides;Amines;2-Aminoalcohols;Yttriumnitratehexahydrate;RegioselectivityAminoalcoholsconstituteanimportantclassofcompoundshavingbothchemicalandbiologicalapplic... Keywords:
Epoxides; Amines; 2-Amino alcohols; Yttrium nitrate hexahydrate; Regioselectivity Amino alcohols constitute an important class of
compoundshaving both chemical and biological applications. They are important pharmacophores present in various inhibitors and are used
as building blocks for the synthesis of biologically active natural products, insecticidal agents and chiral auxillaries for asymmetric
reactions.1a–f They act as starting materials for the synthesis of oxazolines which are useful in the polymer industry.1g Owing to their
widespread applications, the synthesis of amino alcohols has received much attention in recent years.
Traditionally, 2-amino alcohols are prepared by heating an epoxide with an excess of amine at elevated temperature.
The use of a high temperature leads to undesired side reactions and also limits the applicability towards temperature
sensitive substrates. To overcome these drawbacks various promoters such as ZnCl2,2 ScOTf,3 MgBr2OEt2,4 67 9
bismuth salts,5 CoCl2, CuBF4, DIPAT,8 Ti(OiPr)4, 1011 12TaCl5, ZrCl4, Sm(OTf)3, potassium dodecatungstocobaltate,
13 and aluminosilicate14 have been employed for the above transformation. The use of non-conventional techniques
such as microwave irradiation at elevated temperaturehas also been reported.15 Recently, the use of Al(OTf)3 (1 mol %)
as catalyst in toluene at reflux has also been reported.16 Although significant advances have been made
in this area, low regioselectivity, longer reaction time, use of elevated temperature, high catalyst loading, toxic solvents
and lower substrate compatibilitylimit their applications.Thus there is a need to develop an efficient catalytic
protocol for ring opening of various epoxides with aliphatic, aromatic andheteroaromatic amines under ambient conditions
关键词:
环氧化合物;胺; 2 -氨基醇;钇硝酸盐hexahydrate ;区域氨基醇构成的一个重要类
compoundshaving双方化学和生物应用。他们都是重要的pharmacophores目前在各种YZ剂和使用
作为大厦为合成具有生物活性的天然产物,杀虫剂和手性助剂的不对称
reactions.1a - F的,他们作为起始原料为合成oxazolines这是有用的聚合物industry.1g由于其
广泛的应用,合成氨基醇已备受关注,在Z近几年。
传统上, 2 -氨基醇是由暖气一环氧化物与过剩的胺在高温下。
使用高温导致的不良反应和副作用也限制了适用于对温度
敏感的衬底上。为克服这些缺点,各种助剂,如氯化锌, 2 scotf , 3 mgbr2oet2 ,四六七九
铋盐,五氯化钴, cubf4 , dipat , 8钛( oipr ) 4 , 1011 12tacl5 , zrcl4 , Sm (上光学传递函数) 3 ,钾dodecatungstocobaltate ,
13日和aluminosilicate14已受聘为上述转型。使用非传统技巧
如微波辐射在高架temperaturehas也reported.15Z近,使用的Al (光学传递函数) 3 ( 1 mol %时)
为催化剂,在甲苯,在回流亦已reported.16虽然已经取得重大进展
在这方面,低的区域,更长的反应时间,利用高温,高催化剂装填,有毒溶剂
和较低的衬底compatibilitylimit他们applications.thus是有需要发展一个有效率的催化
议定书为开环的各种氧化物与脂肪族,芳香族andheteroaromatic胺的环境条件下