Installation of photolabile carbonyl-protecting groups under neutral conditions without using any other chemical reagents

European Journal of Organic Chemistry

Volumn , Issue 2, 2009, Pages 208-211

  Wang, Pengfei ^a   Wang, Yun ^a   Hu, Ayou ^a   Liang, Xing ^a  

^a UNIVERSITY OF ALABAMA AT BIRMINGHAM   (United States)

Author keywords

Carbonyl compounds; Neutral conditions; Photolabile groups; Protecting groups; Reagent free reactions; Solvent free reactions

Indexed keywords

EID: 58649104426     PISSN: 1434193X     EISSN: 10990690     Source Type: Journal    
DOI: 10.1002/ejoc.200800966     Document Type: Article

References (9)

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4. c) P. Wang, Y. Wang, H. Hu, C. Spencer, X. Liang, L. Pan, J. Org. Chem. 2008, 73, 6152-7.
5. [1,3b] It is likely that a trityl carbocation intermediate is first generated from 1 upon acid treatment. Subsequent nucleophilic attack by the carbonyl oxygen atom led to the corresponding oxonium cation, which cyclized to the desired acetal/ketal. We observed that the dimethyl ketal of 4-(4-methoxyphenyl)butan-2-one failed to react with 1 to produce the desired ketal, whereas the corresponding ketone underwent clean reactions under the same conditions, and the dimethyl ketal readily reacted with other simple 1,3-diols to produce the corresponding 1,3-dioxanes.
6. b) E. V. Gromachevskaya, A. G. Sakhabutdinov, V. G. Kul'nevich, I. S. Arustamova, R. B. Valeev, B. A. Bazhenov, Chem. Heterocycl. Compd. 1991, 27, 502-503.
7. [4b] But the unambiguous structure of 2 is supported by spectroscopic data.
8. b) L. Jurd, J. N. Roitman, Tetrahedron 1979, 35, 1567-1574.
9. a) The product is a mixture of two diastereomers. Similar diastereomeric products were also observed in the reaction of the ketone with 5-methoxy-α,α-diphenylsalicyl alcohol.