OpenLLM-France/wikimedia huggingface dataset:
# Astronomy Centre, University of Sussex

The Astronomy Centre at the University of Sussex, UK undertakes research in Astronomy, Astrophysics and Cosmology.

## The centre today

The Astronomy Centre boasts 12 permanent Faculty members and 12 Postdoctoral Research Fellows, as well as many PhD and MSc students.
Their scientific research interests are tightly focused on the early universe, observational cosmology, large-scale structure formation, galaxy clusters and galactic formation and evolution. These problems are examined with a combination of theoretical, numerical and observational techniques.
Members of the Astronomy Centre have been and are involved in many international collaborations including the Dark Energy Survey, Herschel Space Observatory, LOFAR, Square Kilometre Array, Galaxy And Mass Assembly survey, Planck (spacecraft) and POLARBEAR.

## History

The Astronomy Centre began in 1965 with the founding of an MSc course, run jointly with the Royal Greenwich Observatory, then based at Herstmonceux in Sussex . This link contains also a link to an article by Roger Tayler on the first 30 years of astronomy at Sussex.

## Alumni

The Astronomy Centre has a number of famous former and current members;
* John D. Barrow
* John Gribbin
* Andrew R. Liddle
* William McCrea
* Leon Mestel
* Bernard Pagel
* Martin Rees, Baron Rees of Ludlow
* Roger Tayler
* This article about an organization or institute connected with astronomy is a stub. You can help Wikipedia by expanding it.
* v
* t
* e
# Arachis correntina

Arachis correntina (syn. Arachis villosa Benth. var. correntina Burkart) is a herb native to Argentina and Paraguay. This plant is cited as gene sources for research in plant biology of peanut (Arachis hypogaea).
# Ari Greenberg

Ari David Greenberg (born April 1, 1981 in Malibu, California) is an American world junior champion in contract bridge. A Stanford computer science graduate, Greenberg was previously employed Bridge Base, Google, and Facebook. He currently resides in Menlo Park, California.

## Bridge accomplishments
### Awards

* ACBL King or Queen of Bridge 1999

### Wins

* Grand National Teams Flight B 2001
* World Junior Teams Championship 2005, 2006
* South American Junior Championships 2007

### Runners-up

* World University Team Cup 2006
# 4-hydroxybenzoate polyprenyltransferase

In enzymology, a 4-hydroxybenzoate polyprenyltransferase (EC 2.5.1.39) is an enzyme that catalyzes the chemical reaction
    a polyprenyl diphosphate + 4-hydroxybenzoate $\rightleftharpoons$ diphosphate + a 4-hydroxy-3-polyprenylbenzoate
Thus, the two substrates of this enzyme are a polyprenyl diphosphate and 4-hydroxybenzoate, whereas its two products are diphosphate and 4-hydroxy-3-polyprenylbenzoate.
This enzyme belongs to the family of transferases, specifically those transferring aryl or alkyl groups other than methyl groups. This enzyme participates in ubiquinone biosynthesis.

## Nomenclature

The systematic name of this enzyme class is polyprenyl-diphosphate:4-hydroxybenzoate polyprenyltransferase. Other names in common use include:
* nonaprenyl-4-hydroxybenzoate transferase,
* 4-hydroxybenzoate transferase,
* p-hydroxybenzoate dimethylallyltransferase,
* p-hydroxybenzoate polyprenyltransferase,
* p-hydroxybenzoic acid-polyprenyl transferase,
* p-hydroxybenzoic-polyprenyl transferase, and
* 4-hydroxybenzoate nonaprenyltransferase
# Belgium at the 2022 World Aquatics Championships

Belgium competed at the 2022 World Aquatics Championships in Budapest, Hungary from 17 June to 3 July.

## Open water swimming

Belgium qualified one male open water swimmer.
| Athlete | Event | Time | Rank |
| Logan Vanhuys | Men's 10 km | 1:53:24.5 | 10 |

## Swimming

Belgium entered 4 swimmers.

### Men

| Athlete | Event | Heat | Heat | Semifinal | Semifinal | Final | Final |
| Athlete | Event | Time | Rank | Time | Rank | Time | Rank |
| Louis Croenen | 100 m butterfly | 53.38 | 36 | did not advance | did not advance | did not advance | did not advance |
| Louis Croenen | 200 m butterfly | 1:57.63 | 20 | did not advance | did not advance | did not advance | did not advance |

### Women

| Athlete | Event | Heat | Heat | Semifinal | Semifinal | Final | Final |
| Athlete | Event | Time | Rank | Time | Rank | Time | Rank |
| Valentine Dumont | 100 m freestyle | 55.14 | 20 | did not advance | did not advance | did not advance | did not advance |
| Valentine Dumont | 200 m freestyle | 1:58.86 | 17 | did not advance | did not advance | did not advance | did not advance |
| Valentine Dumont | 400 m freestyle | 4:13.33 | 20 | — | — | did not advance | did not advance |
| Florine Gaspard | 50 m breaststroke | 31.10 | 17 | did not advance | did not advance | did not advance | did not advance |
| Florine Gaspard | 100 m breaststroke | 1:09.22 | 26 | did not advance | did not advance | did not advance | did not advance |
| Fleur Vermeiren | 50 m breaststroke | 30.70 | =9 Q | 30.98 | 15 | did not advance | did not advance |
# Archips limatus

Archips limatus is a species of moth of the family Tortricidae. It is found in Shanxi, China.

## Subspecies

* Archips limatus limatus
* Archips limatus albatus Razowski, 1977
# 2023 European Athletics U23 Championships – Men's 1500 metres

The men's 1500 metres event at the 2023 European Athletics U23 Championships was held in Espoo, Finland, at Leppävaara Stadium on 13 and 15 July.

## Records

Prior to the competition, the records were as follows:
| European U23 record | Jakob Ingebrigtsen (NOR) | 3:28.32 | Tokyo, Japan | 7 August 2021 |
| Championship U23 record | Wolfram Müller (GER) | 3:38.94 | Amsterdam, Netherlands | 14 July 2001 |

## Results
### Heats

Qualification rules: First 6 in each heat (Q) will qualify for the final.
| Rank | Heat | Name | Country | Time | Notes |
| 1 | 1 | Mohamed Attaoui | Spain | 3:44.60 | Q |
| 2 | 1 | Noah Baltus | Netherlands | 3:44.88 | Q |
| 3 | 1 | Maciej Wyderka | Poland | 3:45.20 | Q |
| 4 | 1 | Matthew Stonier | Great Britain | 3:45.47 | Q |
| 5 | 1 | Santtu Heikkinen | Finland | 3:45.53 | Q |
| 6 | 1 | Viktor Idhammar | Sweden | 3:46.31 | Q |
| 7 | 1 | Thomas Piquart | France | 3:47.45 | |
| 8 | 1 | Rick van Riel | Netherlands | 3:48.67 | |
| 9 | 2 | Flavien Szot | France | 3:48.82 | Q |
| 10 | 2 | Filip Ostrowski | Poland | 3:48.88 | Q |
| 11 | 2 | Samuel Pihlström | Sweden | 3:49.02 | Q |
| 12 | 2 | Stefan Nillessen | Netherlands | 3:49.06 | Q |
| 13 | 1 | Matteo Guelfo | Italy | 3:49.29 | |
| 14 | 2 | Pol Oriach | Spain | 3:49.30 | Q |
| 15 | 2 | Jakub Davidík | Czech Republic | 3:49.37 | Q |
| 16 | 2 | Giuseppe Gravante | Italy | 3:49.59 | |
| 17 | 2 | Marcel Tobler | Austria | 3:50.50 | |
| 18 | 2 | Esten Hansen-Møtlerud Hauen | Norway | 3:51.10 | |
| 19 | 2 | Martin Desmidt | France | 3:58.36 | |
| 20 | 1 | Nikita Bogdanovs | Latvia | 4:00.53 | |

### Final

| Rank | Name | Country | Time |
| | Stefan Nillessen | Netherlands | 3:43.35 |
| | Mohamed Attaoui | Spain | 3:43.63 |
| | Samuel Pihlström | Sweden | 3:43.73 |
| 4 | Matthew Stonier | Great Britain | 3:44.31 |
| 5 | Pol Oriach | Spain | 3:44.85 |
| 6 | Filip Ostrowski | Poland | 3:45.01 |
| 7 | Noah Baltus | Netherlands | 3:45.49 |
| 8 | Maciej Wyderka | Poland | 3:45.68 |
| 9 | Santtu Heikkinen | Finland | 3:46.19 |
| 10 | Viktor Idhammar | Sweden | 3:46.33 |
| 11 | Flavien Szot | France | 3:46.64 |
| | Jakub Davidík | Czech Republic | DQ |
# 2023 Open Castilla y León

The 2023 Open Castilla y León was a professional tennis tournament played on outdoor hard courts. It was the 37th edition of the tournament and part of the 2023 ATP Challenger Tour. It took place in El Espinar, Segovia, Spain, between 24 and 30 July 2023.

## Singles main draw entrants
### Seeds

| Country | Player | Rank$^1$ | Seed |
| HUN | Márton Fucsovics | 54 | 1 |
| FRA | Hugo Grenier | 135 | 2 |
| USA | Nicolas Moreno de Alboran | 146 | 3 |
| USA | Emilio Nava | 171 | 4 |
| ITA | Mattia Bellucci | 173 | 5 |
| ESP | Pablo Llamas Ruiz | 180 | 6 |
| FRA | Antoine Escoffier | 188 | 7 |
| LTU | Ričardas Berankis | 194 | 8 |
* $^1$ Rankings as of 17 July 2023.

### Other entrants

The following players received wildcards into the singles main draw:
* David Jordà Sanchis
* George Loffhagen
* Fernando Verdasco
The following player received entry into the singles main draw using a protected ranking:
* Pierre-Hugues Herbert
The following players received entry into the singles main draw as alternates:
* Antoine Bellier
* Gonçalo Oliveira
* Dominik Palán
The following players received entry from the qualifying draw:
* Edas Butvilas
* Miguel Damas
* John Echeverría
* Iñaki Montes de la Torre
* Luca Potenza
* Adrià Soriano Barrera

## Champions
### Singles

* Pablo Llamas Ruiz def. Antoine Escoffier 7–6$^{(11–9)}$, 7–6$^{(7–5)}$.

### Doubles

* Dan Added / Pierre-Hugues Herbert def. Francis Alcantara / Sun Fajing 4–6, 6–3, [12–10].
# 2023 Open Città della Disfida

The 2023 Open Città della Disfida was a professional tennis tournament played on clay courts. It was the 23rd edition of the tournament which was part of the 2023 ATP Challenger Tour. It took place in Barletta, Italy between 3 and 9 April 2023.

## Singles main-draw entrants
### Seeds

| Country | Player | Rank$^1$ | Seed |
| | Alexander Shevchenko | 101 | 1 |
| AUT | Filip Misolic | 150 | 2 |
| ITA | Franco Agamenone | 166 | 3 |
| FRA | Benoît Paire | 170 | 4 |
| ITA | Francesco Maestrelli | 171 | 5 |
| FRA | Laurent Lokoli | 172 | 6 |
| CZE | Zdeněk Kolář | 174 | 7 |
| ITA | Flavio Cobolli | 177 | 8 |
* $^1$ Rankings are as of 20 March 2023.

### Other entrants

The following players received wildcards into the singles main draw:
* Federico Arnaboldi
* Flavio Cobolli
* Gianluca Mager
The following player received entry into the singles main draw as an alternate:
* James McCabe
The following players received entry from the qualifying draw:
* Jacopo Berrettini
* Edoardo Lavagno
* Stefano Napolitano
* Julian Ocleppo
* Gabriele Piraino
* Stefano Travaglia
The following player received entry as a lucky loser:
* Salvatore Caruso

## Champions
### Singles

* Shintaro Mochizuki def. Santiago Rodríguez Taverna 6–1, 6–4.

### Doubles

* Jacopo Berrettini / Flavio Cobolli def. Zdeněk Kolář / Denys Molchanov 1–6, 7–5, [10–6].
# 25th Anniversary

25th Anniversary may refer to:
The Phantom of the Opera at the Royal Albert Hall

## Albums

* 25th Anniversary, by Diana Ross and The Supremes, 1986
* 25th Anniversary, by The Temptations, 1986
* 25th Anniversary (Wolfe Tones album), 1989
* 25th Anniversary, by Magnolia Jazz Band, 1998
* 25th Anniversary, by Bagatelle (band), 2004
* 25th Anniversary, by Pasadena Roof Orchestra, 2008
* 25th Anniversary, by The Nerves, 2001
* 25th Anniversary Album (Shirley Bassey album), 1978
* The 25th Anniversary Album (Lee Kernaghan album), 2017
* 25th Anniversary Collection, by K.C. & The Sunshine Band, 1999
* The ★ Collection: 25th Anniversary Edition, by The Monkees, 1992
* The Twenty-fifth Anniversary Anthology, by The Fixx, 2006
* Unarmed – Best of 25th Anniversary, by Helloween, 2009
* Interpretations: A 25th Anniversary Celebration, by The Carpenters, 1995
* 25th Anniversary Ultimate Best -The One-, by Luna Sea, 2014
# 3-hydroxy-4-oxoquinoline 2,4-dioxygenase

In enzymology, a 3-hydroxy-4-oxoquinoline 2,4-dioxygenase (EC 1.13.11.47) is an enzyme that catalyzes the chemical reaction
    3-hydroxy-1H-quinolin-4-one + O$_2$ $\rightleftharpoons$ N-formylanthranilate + CO
Thus, the two substrates of this enzyme are 3-hydroxy-1H-quinolin-4-one and O$_2$, whereas its two products are N-formylanthranilate and CO.
This enzyme belongs to the family of oxidoreductases, specifically those acting on single donors with O$_2$ as oxidant and incorporation of two atoms of oxygen into the substrate (oxygenases). The oxygen incorporated need not be derived from O$_2$. The systematic name of this enzyme class is 3-hydroxy-1H-quinolin-4-one 2,4-dioxygenase (CO-forming). Other names in common use include (1H)-3-hydroxy-4-oxoquinoline 2,4-dioxygenase, 3-hydroxy-4-oxo-1,4-dihydroquinoline 2,4-dioxygenase, 3-hydroxy-4(1H)-one, 2,4-dioxygenase, and quinoline-3,4-diol 2,4-dioxygenase.
# 285 series

The 285 series (285系, 285-kei) is a sleeper electric multiple unit (EMU) train type operated jointly by Central Japan Railway Company (JR Central) and West Japan Railway Company (JR-West) on the overnight Sunrise Izumo and Sunrise Seto limited express services in Japan. These EMUs were introduced from 10 July 1998 to replace ageing locomotive-hauled "Blue Train" coaches which once operated on separate Seto and Izumo services between Tokyo, Shikoku and the Sanin region.

## Livery

The trains are finished in a livery of "Morning Glow" red and "Morning Mist" beige with "Sun Rise" gold lining.

## Formations

As of 1 April 2015, the fleet consists of five sets, numbered I1 to I5. I1 to I3 are owned by JR-West, and are classified 285-0 series. Sets I4 and I5 are owned by JR Central, and are classified 285-3000 series (the individual cars are numbered in the 3000 range). All sets, I1 to I5, are composed as follows, with two motored ("M") cars and five non-powered trailer ("T") cars. Car 7 and 14 is at the Tokyo (eastern) end.
| Car No. | 1/8 | 2/9 | 3/10 | 4/11 | 5/12 | 6/13 | 7/14 |
| Designation | TNWC' | TNW2 | MN | TNWS | MN2 | TNW | TNWC |
| Numbering | KuHaNe 285 | SaHaNe 285-200 | MoHaNe 285 | SaRoHaNe 285 | MoHaNe 285-200 | SaHaNe 285 | KuHaNe 285 |
The cars of JR Central sets I4 and I5 are numbered in the -3000 series. The motor cars are each fitted with one WPS28A single-arm pantograph. The motor cars in sets I1 and I3 each have two.

## Interior

Each car includes toilet facilities.
* B single-twin berths
* B single berths
* Nobinobi floor space (Upper)
* Nobinobi floor space (Lower)
* Mini saloon area

## Fleet details

The individual build details of the fleet are as shown below.
| Set No. | Manufacturer | Date delivered |
| I1 | Kinki Sharyo | 19 March 1998 |
| I2 | Kinki Sharyo | 15 April 1998 |
| I3 | Kawasaki Heavy Industries | 1 May 1998 |
| I4 | Kinki Sharyo | 8 April 1998 |
| I5 | Nippon Sharyo | 24 April 1998 |

## History

The trains entered service on 10 July 1998, with set I4 forming the down Sunrise Izumo, set I5 forming the down Sunrise Seto, set I3 forming the up Sunrise Izumo, and set I2 forming the up Sunrise Seto.
# 36 Boys

The 36 Boys were a gang of primarily Turkish immigrants from Berlin-Kreuzberg.
The gang was active from the late 1980s until the mid-1990s. Besides Turkish, other nationalities were also represented in the large gang. The gang operated in the area around the Kottbusser Tor to the residential areas between the Naunynstraße and Waldemarstraße, as well as up to the Görlitzer Bahnhof. The graffiti of the 36 Boys were distributed throughout Berlin. In Kreuzberg, they served also to mark the gang's "turf". The gang took its name from the former Berlin postal borough Südost 36 or SO 36. The idea for the name of the gang came from Attila Murat Aydın, a founder of the Berlin rap scene, who was murdered in 2003 by a 76-year-old man who was later acquitted on grounds of self defence.
In addition to the 36 Boys there were the "36 Juniors", who showed a higher potential of violence. In the beginning of the 1990s the 36 Boys fought against turf battles with Nazis and Skinheads in the Jungfernheide park. Other rival gangs were the Warriors from the Schlesisches Tor and the Black Panthers from Wedding. During the May riots in Kreuzberg, the 36 Boys initially joined the Autonomists, but the alliance was short-lived because of the group's lack of political orientation.
In 2007 the Berlin Senate employed former members of the 36 Boys as Kiezläufer ("neighbour walkers") in Kreuzberg to help prevent juvenile delinquency. The area around the Naunynstraße, the centre of the gang, was declared a no-go area by the Senate.
After the dissolution of the gang the former gang members went their separate ways. Some remained in the criminal milieu, others such as the cook Tim Raue - awarded by the Gault Millau - turned to lawful careers. Some became social workers in local housing projects and youth centres. Former member Sinan Tosun has opened a shop near Kottbusser Tor in which he sells clothes with 36 Boys logos. His brother, professional boxer Muzaffer Tosun, was also a member of the 36 Boys, as were the rapper Killa Hakan and the author, film director and media educator Neco Çelik.
In the German media, the gang is depicted as the prototypical gang of immigrant background.
# 3728 IRAS

3728 IRAS, provisional designation 1983 QF, is a stony asteroid from the middle region of the asteroid belt, approximately 20 kilometers in diameter. On 23 August 1983, it was discovered by and later named after IRAS, a spaceborne all-sky infrared survey satellite.

## Classification and orbit

The S-type asteroid is also classified as a CX-type by Pan-STARRS' large-scale survey. It orbits the Sun in the central main-belt at a distance of 2.1–3.2 AU once every 4 years and 4 months (1,576 days). Its orbit has an eccentricity of 0.21 and an inclination of 23° with respect to the ecliptic. The first used precovery was taken at Palomar Observatory in 1950, extending the asteroid's observation arc by 33 years prior to its discovery.

## Rotation period

In August 2008, a photometric lightcurve analysis by U.S. astronomer Brian Warner at his Palmer Divide Observatory (716), Colorado, gave a well-defined rotation period of 8.323±0.002 hours with a brightness amplitude of 0.21 in magnitude (U=3).

## Diameter estimates

According to 12 observations by the discovering Infrared Astronomical Satellite, IRAS, the asteroid has an albedo of 0.12 and a diameter of 19.6 kilometers. The Collaborative Asteroid Lightcurve Link derives similar figures, as do the space-based surveys carried out by the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer. Two publications from the post-cryogenic NEOWISE mission find a larger diameter of 23.4 and 27.5 kilometers, respectively.

## Naming

This minor planet was named for the discovering Infrared Astronomical Satellite (IRAS), a collaboration between the United States (NASA), the Netherlands (NIVR), and the United Kingdom (SERC), which observed more than 250,000 celestial bodies in the infrared at wavelengths between 12 and 100 μm during 10 months in 1983. IRAS has also discovered two other minor planets, the 11-kilometer sized main-belt asteroid (10714) 1983 QG and 3200 Phaethon, a near-Earth and potentially hazardous object, parent body of the Geminid meteor shower, as well as six comets, such as 126P/IRAS, a short-period Jupiter family comet, which was also named after the discovering space observatory. The approved naming citation was published by the Minor Planet Center on 4 May 1999 (M.P.C. 34619).
# 20th Field Artillery Regiment

20th Field Artillery Regiment can refer to:
* 20th Field Artillery Regiment (Canada)
* 20th Field Artillery Regiment (United States)
# 3rd: Love Paradise

3rd: Love Paradise (3rd －Loveパラダイス－) is the third studio album from the J-pop girl idol group Morning Musume, released on March 23, 2000.

## Overview

This was the group's most successful album (with the exception of the "best of" albums) selling 863,300 copies and stayed at the Top 30 in the Oricon charts for 7 weeks. It had two of Morning Musume's top selling singles "Love Machine" and "Koi no Dance Site".
The album was certified Million by the Recording Industry Association of Japan for physical sales of over 1 million copies.

## Legacy

In 2004, Maki Goto would later record a solo version of "Kuchizuke no Sono Ato" for her second solo album 2 Paint It Gold.
# 3rd/5th Battalion Lancashire Fusiliers

The 3rd/5th Battalion Lancashire Fusiliers was a unit of the British Army.

## History

The 3rd/5th Battalion of the Lancashire Fusiliers was a Territorial Force unit formed at Bury on 11 October 1914 as a home depot (third line) unit. It was converted into a second line unit by May 1915 and attached to 197th Brigade, 66th (2nd East Lancashire) Division. It moved to Crowborough in May 1915 and on to Tunbridge Wells in October 1915. It later moved to Colchester in March 1916. The Battalion was posted to the Western Front, landing in at Le Havre on 1 March 1917. It was disbanded in February 1918 and its men distributed to other units.
# 20th Kisei

The 20th Kisei 20th iteration of the Kisei tournament, a tournament in the board game go. It was won by Cho Chikun and held in 1996. The first match was played outside Japan, in Amsterdam, the Netherlands. Chikun won 4 games to 3 over Kobayashi Satoru in the final.

## Tournament

| Round of 16 | Round of 16 | Quarter-finals | Quarter-finals | Semi-finals | Semi-finals | Final | Final |
| Susumu Fukui | 0 | | | | |
| - | 0 | | | | |
| - | 0 | Susumu Fukui | 0 | | |
| | | Kunihisa Honda | 1 | | |
| Kunihisa Honda | 0 | Kunihisa Honda | 1 | | |
| - | 0 | | | | |
| - | 0 | | | Kunihisa Honda | 0 |
| | | | | Cho Chikun | 1 |
| Cho Chikun Honinbo | 0 | | | Cho Chikun | 1 |
| - | 0 | | | | |
| - | 0 | Cho Chikun | 1 | | |
| | | Hideo Otake | 0 | | |
| Hideo Otake | 1 | Hideo Otake | 0 | | |
| Satoshi Yuki | 0 | | | | | | |
| Satoshi Yuki | 0 | | | | | Cho Chikun | 2 |
| | | | | | | Masao Kato | 0 |
| So Kofuku | 0 | | | | | Masao Kato | 0 |
| (automatic berth) | 0 | | | | | | |
| (automatic berth) | 0 | So Kofuku | 0 | | | | |
| | | Koichi Kobayashi | 1 | | | | |
| Koichi Kobayashi Meijin | 1 | Koichi Kobayashi | 1 | | | | |
| Yujiro Hashimoto | 0 | | | | | | |
| Yujiro Hashimoto | 0 | | | Koichi Kobayashi | 0 | | |
| | | | | Masao Kato | 1 |
| Ryu Shikun Tengen | 0 | | | Masao Kato | 1 |
| (automatic berth) | 0 | | | | |
| (automatic berth) | 0 | Ryu Shikun | 0 | | |
| | | Masao Kato | 1 | | |
| Masaki Takemiya | 0 | Masao Kato | 1 | | |
| Masao Kato | 1 | | | | |

## Challenger finals

| Player | 1 | 2 | 3 | T |
| Cho Chikun Honinbo | W+1.5 | W+R | | 2 |
| Masao Kato 9 dan | | | | 0 |

## Finals

| Player | 1 | 2 | 3 | 4 | 5 | 6 | 7 | T |
| Kobayashi Satoru (Kisei) | W+R | | | | W+R | W+R | | 3 |
| Cho Chikun (Challenger) | | W+R | W+R | W+1.5 | | | W+R | 4 |
# 4-Ethyltoluene

4-Ethyltoluene is an organic compound with the formula CH$_3$C$_6$H$_4$C$_2$H$_5$. It is one of three isomers of ethyltoluene, the other two isomers being 3-ethyltoluene and 2-ethyltoluene. All are colorless liquids and all are used for the production of specialty polystyrenes.

## Production and use

Ethyltoluene is produced by ethylation of toluene:
    CH$_3$C$_6$H$_5$ + C$_2$H$_4$ → CH$_3$C$_6$H$_4$C$_2$H$_5$
Over typical acid catalysts, this process gives a mixture of the 2-, 3-, and 4- isomers. Using a modified zeolite catalyst, the alkylation is shape-selective for the 4- isomer.
4-Ethyltoluene is subjected dehydrogenation to give 4-vinyltoluene.