Производные ?-аминокислот, содержащие фрагмент ионной жидкости — регенерируемые органокатализаторы асимметрической альдольной реакции в водной среде

V. Выводы.

1. Предложены подходы к созданию нового типа регенерируемых органокатализаторов асимметрической альдольной реакции в водной среде, содержащих в своем составе фрагменты ионных жидкостей (ИЖ). На их основе синтезированы производные (411)-4-гидрокси-(8)-пролина, (8)-серина, (8)-треонина со свободными карбоксильными группами, а таюке амиды (4К.)-4-гидрокси-(8)-пролина с а, а-дифенил-(8)-валинолом, содержащие алкилзамещепные катионы имидазолия или пиридиния и различные, в том числе фторсодержащие, анионы.

2. Установлено, что синтезированные а-амипокислоты, содержащие анионы Ply, и NTf2″ наряду с длшшоцепными алкильными заместителями, а также амиды пролина, модифицированные фрагментами ИЖ, эффективно катализируют асимметрические альдольиые реакции в водной среде, что позволило осуществить на их основе диастереои энантиоселективный синтез широкого круга хиральных Р-гидроксикарбонильных соединений различного строения.

3. Обнаружено, что разработанные катализаторы легко регенерируются и могут быть использованы в изученных реакциях многократно (до 8 раз) без уменьшения их диастереои энантиоселективности.

4. На основании полученных экспериментальных данных высказано предположение о том, что в предложенных условиях реакции под действием катализаторов, содержащих фрагменты ИЖ, протекают преимущественно на границе раздела водной и органической фаз (фазы реагентов), где, благодаря своей амфифильной структуре, располагается модифицированный ИЖ катализатор.

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