Quadricyclane is a strained polycyclic hydrocarbon that has potential application as an additive to rocket fuel , as well as in the conversion of solar energy . The use of this hydrocarbon, however, is limited by the fact that the substance decomposes at relatively low temperatures (200-300 ° C).
| Quadricyclane | |
|---|---|
 | |
| Are common | |
| Systematic name | Quadricyclane tetracyclo [3.2.0.0 2.7 .0 4.6 ] heptane |
| Chem. formula | C 7 H 8 |
| Physical properties | |
| Molar mass | 92.14 g / mol |
| Density | 0.982 g / cm³ |
| Thermal properties | |
| T. melt. | -44 ° C |
| T. bale. | 108 ° C |
| Optical properties | |
| Refractive index | 1.4830 (26.5 ° C) |
| Classification | |
| Reg. CAS number | 278-06-8 |
| PubChem | |
| Reg. EINECS number | |
| Smiles | |
| Inchi | |
| ChemSpider | |
Content
Structure and Properties
The quadricyclane molecule has a highly stressed structure (78.7 kcal / mol) [1] . In the absence of a catalyst at low temperatures, the isomerization of the quadricyclane proceeds slowly (the half-transformation time at 140 ° C is 14 hours) [2] . Due to the stressed structure and thermal stability, quadricyclane has been studied quite extensively.
Under the action of ultraviolet radiation (~ 300 nm) in the presence of a sensitizer, norbornadiene isomerized into quadricyclane [3] . The reverse transformation of the stressed quadricyclane into norbornadiene proceeds with the release of heat. Due to this property, the reaction was proposed for storing solar energy [4] [5] . The high energy of the quadricycle gave rise to its use as an additive to rocket fuel . However, at temperatures above 200 ° C, the quadricyclane undergoes thermal decomposition, while propulsion systems can operate at temperatures exceeding 500 ° C [6] .
Getting
Quadricyclane is obtained by irradiating norbornadiene in the presence of Michler's ketone [7] . Other sensitizers are also proposed, for example, acetone , benzophenone , acetophenone , etc., however, when using them, the product yield decreases. It is also desirable to use freshly distilled norbornadiene to increase the yield [3] .
Chemical Properties
Quadricyclane reacts with many dienophiles to form 1: 1 adducts [8] . Based on this property, a bioorthogonal reaction was proposed — quadricyclane ligation , which allowed selective modification of protein molecules with low molecular weight labels [9] .
Notes
- ↑ Hall HK, Smith CD, Baldt JH Enthalpies of formation of nortricyclene, norbornene, norbornadiene, and quadricyclane (Eng.) // J. Am. Chem. Soc. - 1973. - Vol. 95 , no. 10 . - P. 3197–3201 . - DOI : 10.1021 / ja00791a022 .
- ↑ Hammond GS, Turro NJ, Fischer A. PHOTOSENSITIZED CYCLOADDITION REACTIONS (Eng.) // J. Am. Chem. Soc. - 1961. - Vol. 83 , no. 22 . - P. 4674–4675 . - DOI : 10.1021 / ja01483a051 .
- ↑ 1 2 Smith CD Quadricyclane (Eng.) // Organic Syntheses. - 1971. - Vol. 51 . - P. 133 .
- ↑ Bren V.A., Dubonosov A.D., Minkin V.I., Chernoivanov V. A. - 1991. - T. 60 , No. 5 . - S. 913-948 .
- ↑ Philippopoulos C., Economou D., Economou C., Marangozis J. Norbornadiene-quadricyclane system in the photochemical conversion and storage of solar energy (Eng.) // Ind. Eng. Chem. Prod. Res. Dev. - 1983. - Vol. 22 , no. 4 . - P. 627-633 . - DOI : 10.1021 / i300012a021 .
- ↑ Striebich RC, Lawrence J. Thermal decomposition of high-energy density materials at high pressure and temperature // J. Anal. Appl. Pyrolysis. - 2003. - Vol. 70 , no. 2 . - P. 339-352 . - DOI : 10.1016 / S0165-2370 (02) 00181-X .
- ↑ Cahill PA, Steppel RN Patent US20040054244 Neopr (2004). Date of treatment January 11, 2013.
- ↑ Petrov VA, Vasil'ev NV Synthetic Chemistry of Quadricyclane (English) // Current Organic Synthesis. - 2006. - Vol. 3 , no. 2 . - P. 215-259 . - DOI : 10.2174 / 157017906776819204 .
- ↑ Sletten EM, Bertozzi CR A Bioorthogonal Quadricyclane Ligation // J. Am. Chem. Soc. - 2011. - Vol. 133 , no. 44 . - P. 17570-17573 . - DOI : 10.1021 / ja2072934 . - PMID 21962173 .