C2-Symmetric diamines and their derivatives as promising organocatalysts for asymmetric synthesis

ثبت نشده
چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Camphor-derived C1-symmetric chiral diamine organocatalysts for asymmetric Michael addition of nitroalkanes to enones.

A series of stable C(1)-symmetric chiral diamines (2a–2l) were conveniently synthesized by condensing exo-(-)-bornylamine or (+)-(1S,2S,5R)-menthylamine with various commercially available Cbz-protected amino acids. Among them, 2a can efficiently promote the Michael addition of nitroalkanes to a broad scope of enones with high yields (up to 96%) and excellent enantioselectivities (up to 98%) un...

متن کامل

Synergistic effects within a C2-symmetric organocatalyst: the potential formation of a chiral catalytic pocket.

This study describes the synthesis of five novel C2-symmetric organocatalysts that facilitate the on-water asymmetric aldol reaction at low catalyst loading (1 mol%) without the use of additives. Each catalyst is composed of two diprolinamide units joined by a symmetric alkyl bridging group allowing for systematic modulation of catalytic site proximity. Typically, catalysts in this manuscript w...

متن کامل

Synthesis of chiral sulfoximine-based thioureas and their application in asymmetric organocatalysis

For the first time, chiral sulfoximine derivatives have been applied as asymmetric organocatalysts. In combination with a thiourea-type backbone the sulfonimidoyl moiety leads to organocatalysts showing good reactivity in the catalytic desymmetrization of a cyclic meso-anhydride and moderate enantioselectivity in the catalytic asymmetric Biginelli reaction. Straightforward synthetic routes prov...

متن کامل

Synthesis of new pyrrolidine-based organocatalysts and study of their use in the asymmetric Michael addition of aldehydes to nitroolefins

New pyrrolidine-based organocatalysts with a bulky substituent at C2 were synthesized from chiral imines derived from (R)-glyceraldehyde acetonide by diastereoselective allylation followed by a sequential hydrozirconation/iodination reaction. The new compounds were found to be effective organocatalysts for the Michael addition of aldehydes to nitroolefins and enantioselectivities up to 85% ee w...

متن کامل

Green and efficient synthesis of trialkyl (E)-3-(3-Oxo-2-3,4-dihydro-2-(1H)-quinoxalinylidene)-prop-1-ene-1,2,3- tricarboxylates using K2CO3-PEG-400 as robust catalytic system

An efficient synthesis of trialkyl (E)-3-(3-Oxo-2-3,4-dihydro-2-(1H)-quinoxalinylidene)-prop-1-ene-1,2,3-tricarboxylate derivatives via a simple three-component reaction between benzene-1,2-diamines with dialkyl acetylenedicarboxylates in the presence of K2CO3-PEG catalytic system at 100 oC was reported. The desired products were obtained in excellent yields (88-92%). Various benzene-1,2-diamin...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2015