CC BY-ND-NC 4.0 · SynOpen 2018; 02(01): 0050-0057
DOI: 10.1055/s-0036-1591932
paper
Copyright with the author

Synthesis of Sterically Protected Isoindoles from ortho-Phthalaldehyde

Michiyasu Nakao
a   Graduate School of Pharmaceutical Sciences, Tokushima University, Sho-machi, Tokushima 770-8505, Japan   Email: ssano@tokushima-u.ac.jp
,
Nanako Nishikiori
a   Graduate School of Pharmaceutical Sciences, Tokushima University, Sho-machi, Tokushima 770-8505, Japan   Email: ssano@tokushima-u.ac.jp
,
Akihito Nakamura
a   Graduate School of Pharmaceutical Sciences, Tokushima University, Sho-machi, Tokushima 770-8505, Japan   Email: ssano@tokushima-u.ac.jp
,
Murasaki Miyagi
a   Graduate School of Pharmaceutical Sciences, Tokushima University, Sho-machi, Tokushima 770-8505, Japan   Email: ssano@tokushima-u.ac.jp
,
Nao Shibata
a   Graduate School of Pharmaceutical Sciences, Tokushima University, Sho-machi, Tokushima 770-8505, Japan   Email: ssano@tokushima-u.ac.jp
,
Syuji Kitaike
a   Graduate School of Pharmaceutical Sciences, Tokushima University, Sho-machi, Tokushima 770-8505, Japan   Email: ssano@tokushima-u.ac.jp
,
Makoto Fukui
b   Department of Preventive Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima 770-8504, Japan
,
Hiro-O Ito
b   Department of Preventive Dentistry, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima 770-8504, Japan
,
Shigeki Sano*
a   Graduate School of Pharmaceutical Sciences, Tokushima University, Sho-machi, Tokushima 770-8505, Japan   Email: ssano@tokushima-u.ac.jp
› Author Affiliations
Further Information

Publication History

Received: 05 December 2017

Accepted after revision: 15 January 2018

Publication Date:
20 February 2018 (online)


Abstract

o-Phthalaldehyde (OPA) reacts with O-protected tris(hydroxyalkyl)aminomethanes in the presence of 1-propanethiol to afford a novel class of stable isoindoles. Steric protection provided by the bulkiness of C 3-symmetric primary amines derived from tris(hydroxymethyl)aminomethane could be significant for the stabilization of 1-alkylthio-2-alkyl-substituted isoindoles derived from OPA. A plausible reaction mechanism is proposed to explain the formation of the isoindole and an isoindolin-1-one by-product.

Supporting Information