Unlock instant, AI-driven research and patent intelligence for your innovation.

Process of quadricyclane production

a quadricyclane and production process technology, applied in the field of quadricyclane production, can solve the problems of increasing sensitizer, significant decrease in quadricyclane production rate, etc., and achieve the highest conversion rate to quadricyclane, increase the photon or quantum efficiency of conversion, and reduce the induction period

Inactive Publication Date: 2004-02-19
EXCITON
View PDF6 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

"The present invention provides a process for carrying out solution-phase photochemical transformations using a less expensive and more efficient process. This process involves using an iron halide-doped mercury arc lamp and ethyl michler's ketone as a sensitizer to convert norbornadiene into quadricyclane. The use of ethyl michler's ketone as a sensitizer reduces the induction period and increases the photon or quantum efficiency of the conversion. The process is carried out at a temperature of about -40.degree.C to about -60.degree.C. The use of ethyl michler's ketone as a sensitizer eliminates the requirement of purified norbornadiene for the highest conversion rates to quadricyclane. The process is significantly less expensive and more efficient in producing quadricyclane, potentially allowing lower cost access to outer space."

Problems solved by technology

However, it has been determined that the use of some prior art sensitizers simultaneously leads to a significant decrease in the rate of quadricyclane production with increased conversion.
Furthermore, the addition of more sensitizer in an effort to gain better efficiencies in the production rate is not preferable, particularly in continuous flow reactors, because of the additional steps required.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Process of quadricyclane production
  • Process of quadricyclane production
  • Process of quadricyclane production

Examples

Experimental program
Comparison scheme
Effect test

example 3

[0047] Irradiations of 1 ml samples of 0.5% Ethyl Michler's Ketone in norbornadiene were carried out with a 400 W high-pressure mercury arc lamp and a 400 W iron halide-doped mercury arc lamp as available from Electro-Lite Corporation, Danbury, Conn. The linear conversion rate was 11.48% per hour for the doped lamp as compared to 9.72% per hour for the undoped lamp. This translates to an improvement in conversion rate of 18% with the iron halide-doped lamp. This transformation was carried out at atmospheric pressure at 60.degree. C.

example 4

[0048] The continuous process of converting to quadricyclane was demonstrated with the continuous flow reactor 12 shown in FIG. 1. The apparatus has a Model J06PM22HGC1 1300 W medium pressure mercury arc lamp with a 6.5 inch arc length as available from Jelight Company, Inc., Irvine, Calif., inside a water cooled quartz well that was centered on a spiral tube containing a continuously pumped norbornadiene solution (1.2 mL / min.), of Ethyl Michler's Ketone (0.40% by weight). The norbornadiene was not previously purified. Samples were collected at fixed eight minute intervals. The conversion to quadricyclane was measured by gas chromatography and the results are plotted in FIG. 3. The plot shows a generally linear conversion of norbornadiene to quadricyclane as a function of time throughout most of the process, which lasted 216 minutes. This continuous process was carried out at 25.degree. C.

[0049] Plot of conversion vs. sample number for a continuous reactor with a nominal 1300 W medi...

example 5

[0050] As can be seen generally in FIG. 4, the high solubility of a sensitizer such as EMK reduces or eliminates the need for purification of the norbornadiene. In parallel experiments in which purified and unpurified samples of norbornadiene were each sensitized with 0.75% by weight EMK and irradiated with a 400W iron halide-doped mercury arc lamp as available from Electro-Lite Corporation, Danbury, Conn., the conversion rate to quadricyclane was in the range of 15-25% greater in the case of purified norbornadiene. In similar experiments in which unpurified norbornadiene sensitized with 3.85% by weight EMK, and purified norbornadiene sensitized with 0.75% by weight EMK were irradiated in parallel, increases relative to unpurified, 0.75% by weight EMK sensitized mixtures, were both in the range of 15-25%. Therefore, the greater amounts of the relatively high solubility EMK sensitizer can be used in place of norbornadiene purification for more efficient quadricyclane production.

[0051...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
wavelength rangeaaaaaaaaaa
wavelength rangeaaaaaaaaaa
temperatureaaaaaaaaaa
Login to View More

Abstract

The present invention relates to a process for efficiently producing quadricyclane by the conversion of norbornadiene. A sensitizer, such as a substituted diaminobenzophenone having a solubility in norbornadiene greater than that of Michler's Ketone, may be added to the norbornadiene to form a solution, wherein the sensitizer decreases the induction period at the beginning of the reaction, increases the photon or quantum efficiency of conversion of norbornadiene to quadricyclane, and increases the rate of conversion at the end of the reaction. If the solution is irradiated with light from a metal halide-doped mercury arc lamp to photochemically transform the norbornadiene to quadricyclane, the conversion is more efficient than when other light sources are utilized. Furthermore, the addition of triethylamine to the solution tends to result in the formation of fewer by-products in the transformation reaction.

Description

RELATED APPLICATION(S)[0001] This application is a divisional application of application Ser. No. 09 / 589,908, filed on Jun. 7, 2000, which disclosure is herein incorporated by reference in its entirety.[0002] The invention claimed herein to the extent funding by the Government contributed to the development thereof may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment of any royalties thereon.[0003] This invention relates to fuels. More specifically, this invention relates to quadricyclane and a highly efficient process for producing quadricyclane.[0004] Quadricyclane, or tetracyclo [2.2.1.0.sup.2,6.0.sup.3,5] heptane, is known in the prior art as a chemical for energy storage, in particular, solar energy storage. Quadricyclane has also been recognized as a potential fuel for internal combustion engines, as described in U.S. Pat. No. 5,076,813; and as a rocket propellant, as described in U.S. Pat. No. 5,616,882. In such applic...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(United States)
IPC IPC(8): C07C5/31
CPCC07C2103/86C07C5/31C07C2603/86
Inventor CAHILL, PAUL A.STEPPEL, RICHARD N.
Owner EXCITON