title: Bifunctional hydrogen-bond donors that bear a quinazoline or benzothiadiazine skeleton for asymmetric organocatalysis.
abstract: Hydrogen-bond (HB)-donor catalysts that bear a 2-aminoquinazolin-4-(1H)-one or a 3-aminobenzothiadiazine-1,1-dioxide skeleton have been developed, and it has been shown that these catalyst motifs act similarly to other HB-donor catalysts such as thioureas. The highly enantioselective hydrazination of 1,3-dicarbonyl compounds was realized even at room temperature with up to 96% ee for 2-aminoquinazolin-4-(1H)-one-type catalysts, which were more effective than the corresponding urea and thiourea catalysts. In addition, benzothiadiazine-1,1-dioxide-type catalysts were shown to promote the isomerization of alkynoates to allenoates with high enantioselectivity. To overcome the problem that the products were obtained as mixtures with the starting alkynoates, we developed the tandem isomerization and cycloaddition of alkynoates for the synthesis of advanced chiral compounds such as bicyclo[2.2.1]heptenes and 3-alkylidene pyrrolidine without a significant loss of enantioselectivity.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Tsubasa
authors.initials: T
authors.lastname: Inokuma
authors.forename: Masaya
authors.initials: M
authors.lastname: Furukawa
authors.forename: Takuya
authors.initials: T
authors.lastname: Uno
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Kohzo
authors.initials: K
authors.lastname: Yoshida
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Yano
authors.forename: Katsumi
authors.initials: K
authors.lastname: Matsuzaki
authors.forename: Yoshiji
authors.initials: Y
authors.lastname: Takemoto
mesh_terms: D000586:Amination; D001581:Benzothiadiazines / Q000138:chemical synthesis / Q000737:chemistry*; D002384:Catalysis; D020650:Combinatorial Chemistry Techniques; D006860:Hydrogen Bonding; D008956:Models, Chemical; D015394:Molecular Structure; D011799:Quinazolines / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism; D013890:Thiourea / Q000737:chemistry
chemical_list: D001581:Benzothiadiazines; D011799:Quinazolines; D013890:Thiourea