References and Citations
References:
Cited in Baran Article
Kajigaeshi, S.; Kakinami, T.; Moriwaki, M.; Fujisaki, S.; Maeno, K.; Okamoto, T. Synthesis 1988, 7, 545-546.
This paper describes the process of α-chlorination of a ketone using benzyltrimethylammonium dichloroiodate. Baran needed only to extrapolate the ideas of this article a little further to apply the given reaction conditions to chlorination of a ketal. This article also succinctly demonstrates the process explained and diagrammed by the leading question.
The following articles cited Kajigaeshi, et al.
- Cobb, J. M.; Grimster, N.; Khan, N.; Lai, J. Y. Q.; Payne, H. J.; Payne, L. J.; Raynham, T.; Taylor, J. Tetrahdron Lett. 2002, 43, 7557-7560.
- Tanner, D. D.; Chen, J. J.; Chen, L.; Luelo, C. J. Am. Chem. Soc. 1991, 113, 8074-8081.
- Croce, P. D.; Ferroccioli, R.; Ritieni, A. Synthesis 1990, 3, 212-213.
Kajigaeshi et al. were referenced in the Baran article because of their work with α-chlorination reactions of ketones. Cobb, Tanner, and Croce all cite Kajigaeshi for this same reason, whether it is for his data, for his methods, or to provide a basis for a new or different method of ketone halogenation. In short, the reactions in all three of these articles involve the conversion of a –CH3 group (a methyl neighboring the carbonyl carbon; thus, an α-methyl) into a –CH2Cl group, effectively replacing one hydrogen with a chlorine atom. Cobb further mentions that an analogous reaction will occur to give α-bromination, but with a lower yield. The popularity of this α-chlorination reaction is so high, Cobb tells us, because α-chloroketones are not cheaply available from commercial sources.
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Citations for Website at Large:
Ege, S. Organic Chemistry: Structure and Reactivity, 5th Ed. Boston: Houghton Mifflin, 2004; pp. 693-694, 558-563.
The Chem 215HH textbook; used for information on ketone halogenation.
O’Malley, D.P.; Li, K.; Maue, M.; Zografos, A.L.; Baran, P.S. J. Am. Chem. Soc. 2007, 129, 4762-4775.
The initial journal article; the basis for all of the work done on this website, including the initial inquiry and investigation into ketone halogenation.
Goyal, A.; Kothari, S. Bulletin of the Chemical Society of Japan 2003, 76, 2335-2339.
Pop, E.; Brewster, M.E.; Bodar, N.; Huang, M.J. International Journal of Quantum Chemistry 1993, 48, 17-24.
These two journal articles were used, to an extent, for the determination of the function of dichloroiodate. Namely, they confirmed the oxidizing function of dichloroiodate within this reaction sequence, and they explained the addition of dithionite, a reducing agent, to quench the reaction.
