1,4-Diazabicyclo[2.2.2]octane, 98%

化学性质

参考文献

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Forms crystalline complexes with organolithium compounds: J. Am. Chem. Soc., 87, 3276 (1965), which show enhanced reactivity, e.g. in the high yield ɑ-metallation of thioanisole by n-BuLi: J. Org. Chem., 31, 4097 (1966).

Forms a stable crystalline complex with H₂O₂, useful as an equivalent to "anhydrous" H₂O₂: reaction with TMS chloride gives bis(TMS) peroxide, a useful OH⁺-equivalent, e.g. in the conversion of aryllithiums to phenols: Synthesis, 633 (1986).

Catalyzes the addition of aldehydes to Michael acceptors at the ɑ-position (Baylis-Hillman reaction): Helv. Chim. Acta, 63, 413 (1984):

For further illustrative example, see: Org. Synth., 75, 106 (1997). Complete reaction often takes several days at ambient temperature, while heating causes lower yields. However, it is greatly accelerated by microwave irradiation: Synlett, 444 (1994). Superior results with reduced reaction times can be achieved in aqueous medium: J. Org. Chem., 66, 5413 (2001). The use as reaction medium of tetramethylene sulfone: Tetrahedron Lett., 45, 1183 (2004), or PEG-400: Tetrahedron Lett., 45, 5865 (2004) has also been advocated. Lithium perchlorate was found to increase the reaction rate dramatically: Tetrahedron Lett., <>< class="boldtxt">40, 1539 (1999), as was a catalytic amount of a metal triflate, particularly La or Sm; conventional Lewis acids were ineffective: J. Org Chem., 63, 7183 (1998). For asymmetric Baylis-Hillman reaction using (1S,2R)-(-)-10,2-Camphorsultam, A15897, as chiral auxiliary, see: J. Am. Chem. Soc., 119. 4317 (1997). See also 3-Quinuclidinol, B21503. For more recent discussion and comparison of different catalysts, see: J. Org. Chem., 692 (2003). In a reinterpretaion of the mechanism, a hemiacetal interemediate has been proposed: J. Org. Chem., 70, 3980 (2005). For reviews of the Baylis-Hillman reaction, see: Tetrahedron, 44, 4653 (1988); 52, 8001 (1996).

Promotes the cleavage of ß-keto esters in refluxing xylene directly to ketones, without the need for prior hydrolysis: J. Org. Chem., 39, 1592, 2647 (1974). Similarly, malonic esters can be cleaved to esters of substituted acetic acids: J. Org. Chem., 41, 208 (1976).

In conjunction with palladium acetate and PEG-400 provides a reusable catalyst system for the Suzuki-Miyaura cross-coupling reaction of boronic acids: J. Org. Chem., 70, 5409 (2005).

Lu, W.; Zhang, G.; Li, J.; Hao, J.; Wei, F.; Li, W.; Zhang, J.; Shao, Z. G.; Yi, B. Polybenzimidazole-crosslinked poly(vinylbenzyl chloride) with quaternary 1,4-diazabicyclo (2.2.2) octane groups as high-performance anion exchange membrane for fuel cells. J. Power Sources 2015, 296, 204-214.

Yarinich, L. A.; Burakova, E. A.; Zakharov, B. A.; Boldyreva, E. V.; Babkina, I. N.; Tikunova, N. V.; Silnikov, V. N. Polybenzimidazole-crosslinked poly(vinylbenzyl chloride) with quaternary 1,4-diazabicyclo (2.2.2) octane groups as high-performance anion exchange membrane for fuel cells. Eur. J. Med. Chem. 2015, 95, 563-573.