Recent advances in the asymmetric phosphoric acid-catalyzed synthesis of axially chiral compounds

• Alemayehu Gashaw Woldegiorgis and
• Xufeng Lin

Beilstein J. Org. Chem. 2021, 17, 2729–2764, doi:10.3762/bjoc.17.185

• 1 mol % CPA 24, 5H-thiazol-4-ones 111 and p-quinone methides generated in situ from propargyl alcohols 110 were incorporated and afforded the axially chiral tetrasubstituted allenes 113 with a chiral thiazolone moiety in high yield (65–97%), high enantioselectivity (76 to >99% ee) and

Highly chemo-, enantio-, and diastereoselective [4 + 2] cycloaddition of 5H-thiazol-4-ones with N-itaconimides

• Shuai Qiu,
• Choon-Hong Tan and
• Zhiyong Jiang

Beilstein J. Org. Chem. 2016, 12, 2293–2297, doi:10.3762/bjoc.12.222

• /bjoc.12.222 Abstract A dipeptide-based urea-amide tertiary amine (DP-UAA) was shown to be an effective Brønsted base catalyst for the first asymmetric annulation reaction between 5H-thiazol-4-ones and N-itaconimides. High levels of enantioselectivity (up to 99% ee) and diastereoselectivity (>19:1 dr

• ) were obtained for a series of spirocyclic 1,4-sulfur-bridged piperidinone-based succinimides. Keywords: [4 + 2] annulation; asymmetric organocatalysis; dipeptide-based Brønsted bases; 5H-thiazol-4-ones; N-itaconimides; Introduction Sulfur-containing tetrasubstituted carbon stereocenters are widely

• prochiral carbon centers can be considered to be one of the most efficient and expedient approach [1][2][3][4]. The development of novel S-containing substrates has therefore attracted the attention of chemists [1][2][3][4]. For example in 2013, Palomo and co-workers introduced 5H-thiazol-4-ones as a new