title: Asymmetric NHC-catalyzed aza-Diels-Alder reactions: highly enantioselective route to α-amino acid derivatives and DFT calculations.
abstract: A facile N-heterocyclic carbene catalytic enantioselective aza-Diels-Alder reaction of oxodiazenes with α-chloroaldehydes as dienophile precursors is reported, with excellent enantioselectivity (ee > 99%) and excellent yield (up to 93%). DFT study showed that cis-TSa, formed from a top face approach of oxodiazene to cis-IIa, is the most favorable transition state and is consistent with the experimental observations.
authors.affiliation: College of Materials, Chemistry and Chemical Engineering, Hangzhou Normal University , Hangzhou 310036, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Yang
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.forename: Richmond
authors.initials: R
authors.lastname: Lee
authors.forename: Yunbo
authors.initials: Y
authors.lastname: Lv
authors.forename: Kuo-Wei
authors.initials: KW
authors.lastname: Huang
authors.forename: Guofu
authors.initials: G
authors.lastname: Zhong
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry*; D001372:Aza Compounds / Q000737:chemistry*; D002384:Catalysis; D061565:Cycloaddition Reaction; D006573:Heterocyclic Compounds, 1-Ring / Q000138:chemical synthesis* / Q000737:chemistry; D006843:Hydrocarbons, Chlorinated / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D000596:Amino Acids; D001372:Aza Compounds; D006573:Heterocyclic Compounds, 1-Ring; D006843:Hydrocarbons, Chlorinated; C030011:carbene; D008697:Methane