Chem. J. Chinese Universities ›› 2024, Vol. 45 ›› Issue (2): 20230473.doi: 10.7503/cjcu20230473

• Organic Chemistry • Previous Articles    

Synthesis of Dihydro-1,3-benzoxazine Compounds via Catalytic Cycloaddition of ortho-Hydroxyphenyl-substituted para-Quinone Methides and Ketimines

SUN Yidan1, LI Xin1,2()   

  1. 1.College of Chemistry,Nankai University,Tianjin 300071,China
    2.Haihe Laboratory of Sustainable Chemical Transformations,Tianjin 300192,China
  • Received:2023-11-13 Online:2024-02-10 Published:2023-12-01
  • Contact: LI Xin E-mail:xin_li@nankai.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(22371219)

Abstract:

The [4+2] cycloaddition reaction between ortho-hydroxyphenyl-substituted para-quinone methides and ketimines was carried out in a phosphoric acid catalytic system. A wide range of dihydro-1,3-benzoxazine derivatives were obtained with good yields and excellent diastereoselectivities. When the catalytic amount of B(C6F53 was added to the reaction system, the yield of the product was maintained and the diastereoselectivity was flipped.

Key words: ortho-Hydroxyphenyl-substituted para-quinone methide, Ketimine, [4+2] Cycloaddition reaction, Dihydro-1, 3-benzoxazine, Diastereoselectivity flipped

CLC Number: 

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