• search hit 1 of 5
Back to Result List

Asymmetric Synthesis of Nonracemic 2-Amino[6]helicenes and Their Self-Assembly into Langmuir Films

  • Alternative ways of preparing nonracemic 2-amino[6]helicene derivatives were explored. The enantioselective [2 + 2 + 2] cycloisomerization of a nonchiral triyne under Ni(cod)(2)/(R)-QUINAP catalysis delivered the enantioenriched (+)-(P)-2-aminodibenzo[6]helicene derivative in 67% ee. An ultimate "point-to-helical" chirality transfer was observed in the cyclization of enantiopure triynes mediated by Ni(CO)(2)(PPh3)(2) affording (-)-(M)- or (+)-(P)-7,8-bis(p-tolyl)hexahelicen-2-amine in >99% ee as well as its benzoderivative in >99% ee. The latter mode of stereocontrol was inefficient for a 2-aminobenzo[6]helicene congener with an embedded five-membered ring. The rac-, (-)-(M)-, and (+)-(P)-7,8-bis(p-tolyl)hexahelicen-2-amines formed Langmuir monolayers at the air water interface featuring practically identical surface pressure vs mean molecular area isotherms. The corresponding Langmuir-Blodgett films on quartz or silicon substrates were characterized by UV vis/ECD spectroscopy and AFM microscopy, respectively.

Export metadata

Additional Services

Search Google Scholar Statistics
Metadaten
Author details:Manfred KarrasORCiDGND, Jan Holec, Lucie Bednarova, Radek Pohl, Bernd SchmidtORCiDGND, Irena G. Stara, Ivo StaryORCiD
DOI:https://doi.org/10.1021/acs.joc.8b00538
ISSN:0022-3263
ISSN:1520-6904
Pubmed ID:https://pubmed.ncbi.nlm.nih.gov/29676572
Title of parent work (English):The journal of organic chemistry
Publisher:American Chemical Society
Place of publishing:Washington
Publication type:Article
Language:English
Date of first publication:2018/05/18
Publication year:2018
Release date:2021/11/30
Volume:83
Issue:10
Number of pages:16
First page:5523
Last Page:5538
Funding institution:Czech Science FoundationGrant Agency of the Czech Republic [16-08294S]; Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences [RVO: 61388963]; German Academic Exchange Service (DAAD-fellowship) [57314603]; Ministry of Education, Youth and Sports of the Czech RepublicMinistry of Education, Youth & Sports - Czech Republic [LM2015073]
Organizational units:Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie
DDC classification:5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften
Peer review:Referiert
Accept ✔
This website uses technically necessary session cookies. By continuing to use the website, you agree to this. You can find our privacy policy here.