1,3,4,6,7,8-Hexahydro-2H-pyrimido[1,2-a]pyrimidin Chemische Eigenschaften,Einsatz,Produktion Methoden
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Beschreibung
1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) is a bicyclic guanidine that has found extensive application in organic chemistry, notably as a powerful catalyst for polymer synthesis and recycling, CO2 utilization, and carboxylic acid derivative synthesis. Bearing both a nucleophilic nitrogen and an electrophilic N?H group, TBD is a multifunctional reagent. It can serve as an organic superbase, an acyl transfer reagent, and a hydrogen bonding activator. It is an excellent catalyst for Michael and Michael-type reactions. The readily available organocatalyst 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) was used for the rapid synthesis of 3-hydroxyisoindolin-1-ones from 3-alkylidenephthalides[1-2].
Chemische Eigenschaften
Light yellow crystalline
Verwenden
1,5,7-Triazabicyclo[4.4.0]dec-5-ene may be used as organocatalyst for aminolysis of esters. It may be used as catalyst for direct addition of P(O)-H bonds (dialkyl phosphites and diphenyl phosphonite) across various activated alkenes. Polymer supported 1,5,7-triazabicyclo[4.4.0]dec-5-ene (PTBD) was used as a base and a reagent scavenger for the synthesis of aryl ethers from phenols and alkyl or aryl halides.
Allgemeine Beschreibung
1,5,7-Triazabicyclo[4.4.0]dec-5-ene, a bicyclic guanidine base, has been found to be an excellent catalyst for Michael and Michael-type reactions. It forms 1:1 complex with lasalocid acid and crystal structure of the complex has been studied by X-ray diffraction, FT-IR spectroscopy and
1H NMR.
l?uterung methode
1,5,7-Triazabicyclo[4.4.0]dec-5-ene crystallises from Et2O but readily forms white crystals of the carbonate. It is a strong base (see pK, i.e. about 100 times more basic than tetramethylguanidine). The picrate has m 220.5-222o (from EtOH). It forms the 5-nitro derivative m 14.5-160o that gives a 5-nitro nitrate salt m 100-101o (from EtOH/Et2O) and a 5-nitro picrate m 144-145o (from H2O) [McKay & Kreling Can J Chem 35 1438 1957, Schwesinger Chimia 39 369 1985, Hilpert et al. J Chem Soc, Chem Commun 1401 1983, Kamfen & Eschenmoser Helv Chim Acta 72 185 1989]. [Beilstein 26 III/IV 60.]
1,3,4,6,7,8-Hexahydro-2H-pyrimido[1,2-a]pyrimidin Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
