1,5,7-triazabicyclo (4.4.0) dec-5-en

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Structural formula
Structural formula of triazabicyclodecene
General
Surname 1,5,7-triazabicyclo (4.4.0) dec-5-en
other names
  • Triazabicyclodecene
  • 1,3,4,6,7,8-hexahydro-2 H pyrimido [1,2-a] pyrimidine
  • TBD
Molecular formula C 7 H 13 N 3
Brief description

white to light yellow crystal powder

External identifiers / databases
CAS number 5807-14-7
EC number 227-367-1
ECHA InfoCard 100,024,880
PubChem 79873
Wikidata Q7840264
properties
Molar mass 139.20 g mol −1
Physical state

firmly

Melting point
pK s value

26.2

solubility

soluble in water, acetonitrile , ethanol , in dimethyl sulfoxide , dimethylformamide , and in other organic solvents, such as. B. toluene , tetrahydrofuran or dichloromethane

safety instructions
GHS labeling of hazardous substances
05 - Corrosive

danger

H and P phrases H: 314
P: 280-305 + 351 + 338-310
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

1,5,7-Triazabicyclo [4.4.0] dec-5-en as bicyclic guanidine is a very strong base that is used in a variety of base-mediated reactions in organic chemistry.

Manufacturing

The cumbersome multi-step synthesis, starting from 1,3-diaminopropane and carbon disulfide (CS 2 )

Synthesis of triazabicyclodecene from 1,3-PDA

and a more recent alternative route with the expensive starting materials tetramethylorthocarbonate and hydrobromic acid is superior to the preparation of triazabicyclodecene from bis (3-aminopropyl) amine and carbon disulfide in the presence of a strong acid, such as. B. para -Toluenesulfonic acid , which provides TBD in 86% yield.

Synthesis of triazabicyclodecene from norspermidine 1

The most efficient synthetic route to 1,5,7-triazabicyclo [4.4.0] dec-5-en seems to be the reaction of guanidine or cyanamide with bis (3-aminopropyl) amine in the presence of strong acids, whereby with elimination of ammonia TBD in 95-97% yield is formed.

Triazabicyclodecene from norspermidine 2

properties

1,5,7-Triazabicyclo [4.4.0] dec-5-en is a white to light yellow crystal powder that dissolves in water, ethanol, acetonitrile and other solvents such as toluene, THF, DMSO and dichloromethane.

As a bicyclic guanidine derivative, TBD is a very strong base whose basicity (pKa value = 26.2) is between that of the amine base 1,1,3,3-tetramethylguanidine TMG (pKa value = 13.6) and the phosphazene P 4 - t -Bu (pKa value = 42.7).

Applications

1,5,7-Triazabicyclo [4.4.0] dec-5-ene catalyzes the isotope exchange H → D in ketones and carboxylic acid esters , such as methyl phenylacetate , already at room temperature with high yields of up to 97%.

H isotope exchange with TBD

As a strong base, TBD catalyzes aldol condensations , such as. B. the reaction of benzaldehyde with heptanal to jasmine aldehyde

Jasminaldehyde synthesis with TBD

The liquid base TBD can be precipitated by introducing CO 2 , isolated by filtration and recovered by heating to 130 ° C. under protective gas.

The aminolysis of carboxylic acid esters is catalyzed by TBD, e.g. B. in the reaction of methyl phenylacetate with benzylamine .

Amidation of methyl phenyl acetate with TBD

Under optimized conditions (30% TBD, 75 ° C) the amide is formed in 94% yield.

Even at low dosages (0.1%), TBD catalyzes the ring-opening polymerization of lactones to form polyesters , such as B. from lactide with the initiator benzyl alcohol in methylene chloride to polylactic acid , in 99% yield within 20 seconds.

ROP of lactide with TBD

With other cyclic esters, such as γ-valerolactone and ε-caprolactone , polymers with useful molecular weights can be obtained in high yields within 0.5 h or 8 h at higher TBD concentrations (0.3 or 0.5%) .

The six-membered δ-valerolactone , but not the considerably more reactive, four-membered β-butyrolactone , also provides the corresponding polyester with low polydispersity (PDI) Q under TBD catalysis .

ROP of delta-valerolactone with TBD

The low Q values ​​of the resulting polymers indicate the presence of living polymerization .

Cyclic carbonates, such as. B. 1,3-Dioxan-2-one (trimethylene carbonate) or nitrogen-containing eight-membered cyclocarbonates can be polymerized and copolymerized with triazabicyclodecene to give functional polycarbonates.

ROP of cyclic carbonates with TBD

Individual evidence

  1. ↑ a b c Entry on 1,5,7-Triazabicyclo [4.4.0] dec-5-ene at TCI Europe, accessed on October 30, 2018.
  2. ↑ a b c d e f data sheet 1,5,7-triazabicyclo [4.4.0] dec-5-en, 98% from Sigma-Aldrich , accessed on October 30, 2018 ( PDF ).
  3. ^ A b C. Sabot, KA Kumar, C. Antheaume, C. Mioskowski: Triazabicyclodecene: An effective isotope exchange catalyst in CDCl 3 . In: J. Org. Chem. Band 72 , no. 13 , 2007, p. 5001-5004 , doi : 10.1021 / jo070307h .
  4. ↑ Product Information: 1,5,7-Triazabicyclo [4.4.0] dec-5-ene from Cayman Chemical, accessed October 30, 2018.
  5. ↑ a b c d M.K. Kiesewetter, MD Scholten, N. Kirn, RL Weber, JL Hedrick, RM Waymouth: Cyclic guanidine organic catalysts: What is magic about triazabicyclodecene? In: J. Org. Chem. Band 74 , no. 24 , 2009, p. 9460-9496 , doi : 10.1021 / jo902369g .
  6. ↑ A. Huczynski, B. Brzezinsky, T. Furukawa: 1,5,7-Triazabicyclo [4.4.0] dec-5-ene . In: e-EROS Encyclopedia of Reagents for Organic Synthesis . 2014, doi : 10.1002 / 047084289X.rn00786.pub2 .
  7. ↑ AF McKay, M.-E. Kreling: Δ 8 -hexahydro-1,4,8-pyrimidazole, Δ 9 -1,5,9-triazabicyclo (4.4.0) decene, and Δ 9 -1,4,9-triazabicyclo (5.3.0) decene . In: Can. J. Chem. Volume 35 , no. 12 , 1957, pp. 1438-1445 , doi : 10.1139 / v57-190 .
  8. ↑ FP Schmidtchen: Synthesis of symmetrically substituted bicyclic guanidines . In: Chem. Ber. tape 113 , no. 6 , 1980, pp. 2175-2182 , doi : 10.1002 / cber.19801130612 .
  9. ↑ Patent EP0198680A1 : Guanidines preparation. Applied on April 11, 1986 , published October 22, 1986 , applicant: BP Chemicals Ltd., inventor: R. A'Court. ‌
  10. ↑ S. Usachev, A. Gridnev: Convenient preparation of bicyclic guanidines . In: Synth. Commun. tape 41 , no. 24 , 2011, p. 3683-3688 , doi : 10.1080 / 00397911.2010.519848 .
  11. ↑ T. Ishikawa: Superbases for Organic Synthesis: Guanidines, Amidines, Phosphazenes and Related Organocatalysts . John Wiley & Sons, Chichester, UK 2009, ISBN 978-0-470-51800-7 .
  12. ^ I. Cota, F. Medina, JE Sueiras, D. Tichit: 1,5,7-Triazabicyclo [4.4.0] dec-5-ene (TBD) an efficient homogeneous catalyst for aldol condensation reactions. Study of the catalyst recovery and reusability using CO2 . In: Tetrahedron Lett. tape 52 , no. 3 , 2011, p. 385-387 , doi : 10.1016 / j.tetlet.2010.11.032 .
  13. ↑ C. Sabot, KA Kumar, S. Meunier, C. Mioskowski: A convenient aminolysis of esters catalyzed by 1,5,7-triazabicyclo [4.4.0] dec-5-ene (TBD) under solvent-free conditions . In: Tetrahedron Lett. tape 48 , no. 22 , 2007, p. 3863-3866 , doi : 10.1016 / j.tetlet.2007.03.146 .
  14. ↑ RC Pratt, BGG Lohmeijer, DA Long, RM Weymouth, JL Hedrick: Triazabicyclodecene: A simple bifunctional organocatalyst for acyl transfer and ring-opening polymerization of cyclic esters . In: J. Amer. Chem. Soc. tape 128 , no. 14 , 2006, p. 4556-4557 , doi : 10.1021 / ja060662 + .
  15. ↑ L. Simón, JM Goodman: The mechanism of TBD-catalyzed ring-opening polymerization of cyclic esters . In: J. Org. Chem. Band 72 , no. 25 , 2007, p. 9656-9662 , doi : 10.1021 / jo702088c .
  16. ^ S. Venkataraman et al .: A simple and facile approach to aliphatic N-substituted functional eight-membered cyclic carbonates and their organocatalytic polymerization . In: J. Amer. Chem. Soc. tape 137 , no. 43 , 2015, p. 13851-138460 , doi : 10.1021 / jacs.5b06355 .