Process for asymmetric intramolecular [3+2] cyclo-addition of hydrazones
AssigneeJapan Science and Technology Agency
InventorsShu Kobayashi, Yasuhiro Yamashita, Haruro Ishitani
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Abstract
An intramolecular [3+2] cycloaddition reaction of a hydrazone is carried out under a mild condition with a high stereoselectivity and yield by reacting a hydrazone derivative in the presence of an asymmetric catalyst system obtained by mixing a zirconium alkoxide represented by the following formula (I): Zr(OR)4 (I) (wherein R is a hydrocarbon group which may have a substituent) with a binaphthol derivative represented by the following formula (II): (wherein Y1 and Y2 are each identical or different and denote a hydrogen atom or a halogen atom, and at least one of Y1 and Y2 denotes a halogen atom).
Claims5
A process for an asymmetric intramolecular [3+2] cycloaddition reaction of a hydrazone which comprises reacting a hydrazone derivative represented by the following formula (III):
- wherein R1, R2, R3, R4 and R5 are each identical or different and denote a hydrogen atom or a hydrocarbon group which may have a substituent or a hetero atom, R1 and R2, R3 and R4 may be linked to form a ring by a hydrocarbon chain which may have a substituent or a hydrocarbon chain which has a hetero atom, and X denotes a hetero atom or a hydrocarbon chain which may have a substituent or a hetero atom, in the presence of an asymmetric catalyst system obtained by mixing a zirconium alkoxide represented by the following formula (I):
- Zr(OR)4 (I)
- wherein R is a hydrocarbon group which may have a substituent with a binaphthol derivative represented by the following formula (II):
- and
- wherein Y1 and Y2 are each identical or different and denote a hydrogen atom or a halogen atom, and at least one of Y1 and Y2 denotes a halogen atom, to produce a cycloaddition reaction product.
Dependencies are inferred from the claim text.