201249852 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種製備三烷基鎵之方法。 【先前技#f】 h者行動電这及光通訊技術之進步，對化合物半導體之 需求正在迅速增長，其係用於高速電子裝置，例如，高電 子遷移率電晶體（HEMT)、異質接面雙極電晶體（HBT)、半 導體雷射器、DVD、光學裝置（如白藍超高強度LED)及其 他應用。 一般而言，第12族及第13族金屬之烷基衍生物，且特定 言之曱基或乙基衍生物係常用作化合物半導體之金屬有機 前體。特定言之，對用於藉由利用第15族元素（如氮、 砷、鎵及其類似物）之MOCVD製備化合物半導體之三烷基 鎵存在巨大需求。 一種製備三烷基鎵之先前技術方法之典型實例係使烷基 齒化物與鎵-鎂混合物或鎵-鎂合金反應。該方法在允許可 輕易購買之高純度金屬鎵及金屬鎂以直接使用，且不需要 使用必須小心的試劑中係有利的。因為使用鎵-鎂合金作 為起始物質導致三烷基鎵之產物比使用鎵-鎂混合物具有 更高之產率’所以諸多先前技術方法使用鎵-鎂合金。 使用錄鎂合金之方法需要藉由加熱製備合金之製程。然 而’難以製備均一的鎵_鎂合金。在大多數情況中，使用 埃烧與合金反應。在烧基_化物中，蛾烧最具反應性。然 而’換院比溴烷及氣烷價格高。此外，由於三甲基鎵與碘 163598.doc 201249852 而且，块 曱烧沸點接近’難以自蛾曱貌中分離三曱基錄 烷及溴烷係有毒及/或臭氧消耗性。 因此，希望提供-種製備三甲基鎵之方法其可以高產 率進行，且使用氣烷代替溴烷或碘烷時具有可接受=速 率。 製備三烷基鎵另-種方法係基於三鹵化鎵與格利雅 (Gngnard)試劑之反應》然而，始自三鹵化鎵之方法經濟 上所受關注較少，此係因為三卣化鎵相當貴。此外三函 化鎵係非常易腐蝕及吸濕，需要特殊設備且無氧接觸下操 作。 已描述藉由使金屬鎵（非與鎂混合或製成合金）與氣烷反 應製備二烧基鎵之方法。然而，其性能極低；參見201249852 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for preparing a trialkyl gallium. [Previous technology #f] h mobile phone and the advancement of optical communication technology, the demand for compound semiconductor is growing rapidly, it is used in high-speed electronic devices, such as high electron mobility transistor (HEMT), heterojunction Bipolar transistors (HBT), semiconductor lasers, DVDs, optical devices (such as white-blue ultra-high-intensity LEDs) and other applications. In general, alkyl derivatives of Group 12 and Group 13 metals, and in particular thiol or ethyl derivatives, are commonly used as metal organic precursors for compound semiconductors. In particular, there is a great demand for a trialkylgallium for preparing a compound semiconductor by MOCVD using a Group 15 element such as nitrogen, arsenic, gallium, and the like. A typical example of a prior art process for preparing trialkyl gallium is to react an alkyl dentate with a gallium-magnesium mixture or a gallium-magnesium alloy. This method is advantageous in allowing the use of readily available high purity metal gallium and magnesium metal for direct use without the need to use reagents that must be handled with care. Because gallium-magnesium alloys are used as starting materials to result in higher yields of trialkyl gallium products than with gallium-magnesium mixtures, many prior art methods use gallium-magnesium alloys. The method of using a magnesium alloy requires a process for preparing an alloy by heating. However, it is difficult to prepare a uniform gallium-magnesium alloy. In most cases, the burnt and alloy reactions are used. In the alkyl group, the moth is most reactive. However, the price of replacement is higher than that of bromine and ethane. In addition, due to trimethylgallium and iodine 163598.doc 201249852, the boiling point of the block is close to that it is difficult to separate the tridecyl- and the bromine-based toxic and/or ozone-depleting properties from the moth. Accordingly, it would be desirable to provide a process for the preparation of trimethyl gallium which can be carried out at high yields and which has acceptable = rate when using a gas alkane instead of a bromane or iodine. The other method for preparing trialkyl gallium is based on the reaction of gallium trihalide with Gngnard reagent. However, the method from the gallium trihalide is less economically concerned, because the gallium trichloride is quite expensive. . In addition, the tri-functional gallium system is very corrosive and hygroscopic, requiring special equipment and operating under oxygen-free contact. A method of preparing a gallium-doped gallium by reacting metal gallium (not mixed with magnesium or alloyed) with a gas alkane has been described. However, its performance is extremely low; see
Storawieski and Klabunde, Appl. Organometallic Chem. 3 (1989) 3 第 219至 224 頁。 【發明内容】 現已發現假設使用合適觸媒’可由金屬鎵與溴烷製備三 烧基嫁。發現合適觸媒係路易斯酸（Lewis acid)。 因此，本發明係關於一種製備三烷基鎵之方法，其包括 以下步驟：⑴在無金屬鎂存在且在路易斯酸觸媒之存在 下，使金屬鎵與氯烷反應，及（ii)使步驟（i)之產物與烷基 金屬反應。 因此該方法允許以高產率，始自金屬鎵及氣烷製備三烷 基錄。 而且，本發明之方法不要求使用需要熱解以獲得三烷基 163598.doc -4· 201249852 鎵的醚溶劑。 根據本發明之方法中夕银 . 之第一步驟包括在路易斯酸觸媒之 存在下’金屬鎵與氯烷之及 夂應在此步驟中不需要Mg或 其他鹼土金屬或鹼金屬。 由此步驟產生之產物係三氣化二炫基鎵；二氣化统基録 及氯化二院基鎵之混合物。 可使用任何金屬鎵。例如’可使用具有99.9%(3N)或更 高純度之市售鎵°市售鎵具有至多7N之純度。 藉由MOCVD製備之化合物半導體之電子性能及光學性 能係受起始有機金屬化合物之純度極大影響。因此，希望 製備高純度三絲鎵。因為所得之三録鎵之純度受起始 鎵純度影響，故較佳使用高純度鎵。 鎵之純度較佳係99.999%(5N)或更高，且特別佳係 99.9999%(6N)或更高。具有5N或更高純度之高純度鎵可如 上所述購得。難以購買低K4N純度之Ga。 合適氣烷係氣烷，且較佳係Ci4氣烷。合適氣烷之 具體實例係氣曱烷、氣乙烷、正氣丙烷、異氣丙烷、正氣 丁烷、異氣丁烷、第二氣丁烷、第三氯丁烷及其組合。氯 甲烧與氯乙烧係最佳氯烧。 較佳的路易斯酸觸媒係含鋁、鎵及錫之路易斯酸，更佳 係鋁、鎵及錫之溴化物、碘化物、硫酸鹽、三氟甲磺酸 鹽、烷基磺酸鹽（如甲基磺酸鹽）及芳基磺酸鹽（如對甲苯磺 酸鹽及苯基磺酸鹽）。合適路易斯酸之具體實例係GaBr3、 Gal3、AlBr3、SnBr4、A12(S04)3、Al(MeS03)3、Al(PhS03)3、 163598.doc 201249852Storawieski and Klabunde, Appl. Organometallic Chem. 3 (1989) 3 pp. 219-224. SUMMARY OF THE INVENTION It has now been discovered that the use of a suitable catalyst' can be used to prepare a tridentate graft from a metal gallium and a bromine. A suitable catalyst was found to be Lewis acid. Accordingly, the present invention is directed to a method of preparing a trialkyl gallium comprising the steps of: (1) reacting metal gallium with chloroalkane in the absence of metallic magnesium and in the presence of a Lewis acid catalyst, and (ii) causing the step The product of (i) is reacted with an alkyl metal. Therefore, this method allows the preparation of a trialkyl group starting from metal gallium and alkane in high yield. Moreover, the process of the present invention does not require the use of an ether solvent that requires pyrolysis to obtain trialkyl 163598.doc -4·201249852 gallium. The first step of the silver in accordance with the method of the present invention comprises the presence of a metal or a mixture of metal gallium and chloroalkane in the presence of a Lewis acid catalyst. Mg or other alkaline earth metal or alkali metal is not required in this step. The product produced by this step is a mixture of three gasified dihydrogen gallium; a gasification system of two gasification systems and a gallium chloride. Any metal gallium can be used. For example, commercially available gallium having 99.9% (3N) or higher purity can be used, and commercially available gallium has a purity of at most 7N. The electronic properties and optical properties of the compound semiconductor prepared by MOCVD are greatly affected by the purity of the starting organometallic compound. Therefore, it is desirable to prepare high purity trifilium gallium. Since the purity of the obtained gallium is affected by the purity of the starting gallium, high purity gallium is preferably used. The purity of gallium is preferably 99.999% (5N) or higher, and particularly preferably 99.9999% (6N) or higher. High purity gallium having a purity of 5 N or higher can be purchased as described above. It is difficult to purchase Ga with a low K4N purity. A suitable naphthalene is a gas alkane, and is preferably a Ci4 gas alkane. Specific examples of suitable olefins are gas decane, ethane ethane, n-gas propane, isogasopropane, n-butane, isobutane, second butane, third chlorobutane, and combinations thereof. Chloroform and chloroethene are the best chlorine burners. Preferred Lewis acid catalysts are Lewis acids containing aluminum, gallium and tin, more preferably aluminum, gallium and tin bromide, iodide, sulfate, triflate, alkyl sulfonate (eg Methanesulfonate) and arylsulfonates (such as p-toluenesulfonate and phenylsulfonate). Specific examples of suitable Lewis acids are GaBr3, Gal3, AlBr3, SnBr4, A12(S04)3, Al(MeS03)3, Al(PhS03)3, 163598.doc 201249852
Al(pTolS03)3、Ga2(S04)3、Ga(MeS03)3 ' Ga(PhS〇3)3 及Al(pTolS03)3, Ga2(S04)3, Ga(MeS03)3'Ga(PhS〇3)3 and
Ga(pTolS〇3)3 » 更佳的路易斯酸觸媒係GaBr3、Gal3、AlBr3及SnBr4。最 佳觸媒係AlBr3。 該路易斯酸觸媒可如此添加至反應混合物中，或可藉由 添加例如I2或Βι*2至反應混合物中而原位形成。後者係特別 有利於原位形成Gal3及GaBr3。 該反應較佳係在30至20(TC之範圍内之溫度下進行，更 佳係35至150°C，最佳係40至120。(：。 在該等溫度下，鎵係呈液態（熔點：29.8t：)。此意味著 不需要溶劑’此係本發明之方法之另一優點。 然而’如基於某種原因需要存在溶劑’則較佳使用烴溶 劑。合適溶劑之實例係飽和脂肪族烴，諸如戊烷、己烷、 庚烧、辛烷、壬烧、癸烷、—烧及十二烷；飽和脂環族 烴’如環己烷及環庚烷；及芳香族烴，諸如甲苯、二甲 笨、三曱苯、乙苯、乙基曱苯及茚。較佳的烴係可容易地 自所得之三烷基鎵中分離之彼等，更佳係具有顯著不同於 三烷基鎵之沸點之彼等。 較佳以相對於金屬鎵為1至10000莫耳％，更佳係1〇〇至 5000莫耳％，及最佳係130至500莫耳％的量，使用氣烧。 較佳以相對於金屬鎵之0.00001至1〇〇〇，更佳係〇」至 100，最佳係2至30莫耳。/〇之量使用該觸媒。 藉由在惰性氣體環境下將鎵、氣烷、觸媒及可選之溶劑 引入反應容器中，進行該方法。可以任何形式及任何順序 163598.doc 201249852 添加此類化合物》較佳地，首先添加鎵，接著添加氯烷。 如果在添加條件下，氣烷係氣態，則可藉由用氣烷淨化反 應器，及最後在大氣壓或更高壓力下將氯烷饋入反應器 中，添加其。亦可在氯烷係液態時之壓力下或溫度條件 下，呈液體添加其》或者，可呈含於與反應混合物相容之 溶劑（較佳係烴溶劑）中之溶液形式添加氯烷，或在路易斯 酸觸媒之存在下，在真空下經由熔融之Ga使其起泡。 該觸媒或（在原位形成觸媒之情況下）其前體可在添加氯 烷之前或之後引入。如果在添加氣烷之後添加，其係可分 若干部分在反應期間加料。或者，其可在開始時以一份式 添力σ ^ 本發明之方法之第二步驟包括在第一步驟形成之三氣化 二烷基鎵與金屬鎵之反應，以形成三烷基鎵。二烷基金屬 氯化物、烷基金屬氣化物、或金屬齒化物氣化物將作為副 產物形成。 合適烷基金屬之實例係烷基鋁、烷基鎂及烷基锂。更佳 地，該烷基金屬係烷基鋁，甚至更佳係三烷基鋁。 該烧基金屬之炫基可包括碳原？，更佳】至々個 碳原子。該烧基金屬之燒基較佳係與在先前步驟中使用之 氣烷之烷基相同。甲基係最佳的烷基；三曱基鋁及三乙基 鋁係最佳的烷基金屬* 一 較佳以相對於在第 10000，更佳 30至 500， 該烧基金屬。 一步驟中使用之金屬鎵為10至 及最佳70至4〇〇莫耳％之量，使用 163598.doc 201249852 ，亦不需要溶劑。然而，如基於某種原因 則較佳使用烴溶劑。合適溶劑之實例係飽 戊燒、己烧、庚院、辛烧、壬烧、癸烧、 在該步驟期間 需要存在溶劑， 和脂肪族烴，如 =一烷及十二烷；飽和脂環族烴，如環己烷及環庚烷；及 芳香族匕，諸如甲苯、苯、三，苯、乙苯、乙基甲苯 及節。較㈣㈣可容易地自所得之三院基鎵t分離之彼 等，更佳係具有顯著不同於該三甲基鎵之沸點之彼等。 考慮二氣化二烷基鎵、烷基金屬及所使用之可選溶劑之 類型及其他因素’選擇合適反應溫度’以有效進行該反 應通常在約0。至200t：，較佳約20。至約1 50。(：，及更佳 約30°至120。(：下，進行該反應。 反應後該反應器之溫度可能增加，以蒸顧所製備之三 烧基錄。 該方法之兩個步驟可在同一反應器中進行。或者，如果 需要’可在用於步驟（ii)之前，蒸顧、再結晶、或以其他 方式純化該中間產物烷基鎵。 藉由本發明之方法獲得之三烷基鎵適宜用於製備半導體 裝置，例如，基於氮化鎵之半導體。 由該方法之第一步驟所得之三氣化二烷基鎵發現可用作 用於半導體製造及用於合成其他Ga化合物之前體。因此本 發明亦係關於一種製備三氯化二烷基鎵之方法。 【實施方式】 實例 實例1 163598.doc 201249852 將Ga(12.00 g，172.1 mmol)裝填入50 ml三頸反應燒瓶 中。該燒瓶係用MeCl淨化（抽空及用MeCl充滿之4次循 環），且將其置於油浴中。施加0.3 bar之MeCl超壓。將該 油浴加熱至100。(：，且在攪拌下將i2 (4.37 g，17·2 mmol)歷 時4〇分鐘添加至Ga。 在100°C下攪拌該反應混合物π小時。所獲得之反應混 合物具有透明琥珀色液體之外觀及具有少量未反應之Ga。 所得之三氯化二烷基鎵在室溫下，在約40小時内自反應混 合物结晶。 將包含結晶之三氯化烷基鎵之該燒瓶移入手套箱。添加 二甲基銘（TMAL ’ 3 ml)，以溶化該混合物，且於用吸液管 移除未反應之Ga(0·85 g;表示第一反應步驟中生成三氣化 二烷基鎵的轉化率為93%)之後，將其轉移入置於油浴中之 100 ml二頸燒瓶中。在12分鐘内將殘留之TMAL(全部為 37·2 g，5 16.4 mmol)添加至燒瓶中。 蒸餾所獲得之反應混合物，以獲得18 25 g透明產物。ιΗ NMR表明該產物含有約4 m〇i〇/0 Mel及96 mol0/〇三甲基鎵。 基於第一步驟中所使用Ga之量，粗三曱基鎵之產率係92% 及基於第一步驟中所反應Ga之量，粗三甲基鎵之產率係 99% 〇 實例2 用 MeCl(約 0.3 bar)淨化包含 Ga(8.〇〇 g，114 7 mm〇1)之 5〇ml三頸燒瓶，且加熱至5(rc。用注射器在22分鐘内添加 >臭（約 0.8 ml ’ 2.52 g，15.8 mmol)至該燒版中。 163598.doc -9- 201249852 添加全部Br2之後，該油浴之溫度升至i〇〇°c (該反應混 合物之内部溫度係951：)。在l〇〇°C下攪拌20小時後，0.73 g Ga保持未反應（轉化率為91 %)。利用吸液管將未反應之 Ga自該反應混合物中移除。 將包含結晶之三氣化二烷基鎵之該燒瓶轉移至手套箱中 且置於油浴中。將具有接收瓶之冷凝器與該燒瓶相連，且 逐漸添加TMAL (24.82 g，344.1 mmol)至該反應混合物 中。在添加開始時，該澄清透明混合物變為灰色懸浮液。 蒸餾所獲得之反應混合物以獲得10.36 g透明產物（90.2 mmol，基於與MeCl之反應中使用之Ga為79%產率及基於 所反應之Ga為86.5%產率）》根據1H NMR光譜中之峰面 積，該產物具有99%之純度；MeBr(0.9 mol%)為主要雜 質。 實例3 用 MeCl(約 0.3 bar)淨化含有 Ga(12.00 g，172.1 mmol)及 AlBr3 (12.00 g，45.0 mmol)之 100 ml二頸燒瓶。用 MeCl充 滿該燒瓶後，AlBr*3變為液體。每小時用MeCn快速沖洗該 反應瓶以移除氣體副產物。第一天，在1 〇〇eC下攪拌該反 應混合物5小時’且殘留約〇·5 g Ga未反應。在室溫下保持 該混合物整夜後，第二天在1〇0〇C下用MeCl再持續反應2小 時。極少量之Ga (<0·〇5 g)仍在透明液體產物中可見，在 100°C下之全部反應時間係7小時。 將包含結晶之三氣化二烷基鎵結晶之該燒瓶轉移入手套 箱中且置於油浴令。將具有接收瓶之冷凝器與該燒瓶相 163598.doc •10· 201249852 連’且逐漸添加TMAL (37·2 g，516.4 mmol)至該反應混合 物中。 添加約10 ml TMAL後，將反應溫度自26°C升至約 80 C ’且澄清透明溶液變為灰色懸浮液。添加全部TMAL 後’該油浴溫度升至120°C，且收集蒸餾物（沸點62至72t) 以獲得17.02 g(i 48.2 mmol，基於第一步驟中使用之Ga為 86¼產率）澄清透明產物。當油浴溫度係ι〇4^時，開始蒸 顧°根據1H NMR，該產物具有97%純度，全部峰面積之 1.5%由MeBr貢獻’其對應於4.5 mol% MeBr污染。室溫下 保存該底部物質（不攪拌）整夜，少量灰色固體沉澱出及該 等底部物質係透明。 比較實例 用Ga (0.77 g’ 11 mmol)裝填50 ml不銹鋼反應器（不攪 拌）’密封’用MeCl加壓至3.9 atm。室溫（0.4 g，7.9 mmol MeCl)下且加熱至40°C達3天《該反應器冷卻至室溫後，該 壓力係3.8 atm。該反應器僅含Ga金屬；無產物形成。 此實驗顯示，對於Ga金屬與氯烷之反應而言，路易斯酸 觸媒是必需的。若無此等觸媒（如在本發明比較實例中）， 則不會發生反應。 163598.doc 11Ga(pTolS〇3)3 » More preferred Lewis acid catalysts are GaBr3, Gal3, AlBr3 and SnBr4. The best catalyst is AlBr3. The Lewis acid catalyst can be added to the reaction mixture as such, or can be formed in situ by adding, for example, I2 or Βι*2 to the reaction mixture. The latter is particularly advantageous for the in situ formation of Gal3 and GaBr3. The reaction is preferably carried out at a temperature in the range of 30 to 20 (TC), more preferably 35 to 150 ° C, and most preferably 40 to 120. (: At these temperatures, the gallium is liquid (melting point) : 29.8t:). This means that no solvent is required. This is another advantage of the method of the present invention. However, if a solvent is required for some reason, a hydrocarbon solvent is preferably used. Examples of suitable solvents are saturated aliphatics. Hydrocarbons such as pentane, hexane, heptane, octane, decane, decane, decyl and dodecane; saturated alicyclic hydrocarbons such as cyclohexane and cycloheptane; and aromatic hydrocarbons such as toluene , dimethyl benzene, triterpene benzene, ethyl benzene, ethyl benzene and hydrazine. Preferred hydrocarbons can be easily separated from the obtained trialkyl gallium, and more preferably have a significant difference from the trialkyl group. The boiling point of gallium is preferably from 1 to 10,000 mol%, more preferably from 1 to 5,000 mol%, and preferably from 130 to 500 mol%, based on the metal gallium. Preferably, the catalyst is used in an amount of from 0.00001 to 1 〇〇〇, more preferably from 〇 to 100, and most preferably from 2 to 30 摩尔. The method is carried out by introducing gallium, alkane, a catalyst and an optional solvent into the reaction vessel under an inert atmosphere. Such compounds may be added in any form and in any order 163598.doc 201249852. Preferably, first Adding gallium, followed by adding chloroalkane. If the gas is in a gaseous state under the conditions of addition, the reactor can be purified by feeding the reactor with a gas stream, and finally feeding the chloroalkane into the reactor at atmospheric pressure or higher. Alternatively, the chloroalkane may be added as a liquid under a pressure of a chloroalkane liquid or under a temperature condition, or may be added as a solution contained in a solvent (preferably a hydrocarbon solvent) compatible with the reaction mixture. Alternatively, it may be bubbled under vacuum in the presence of a Lewis acid catalyst via molten Ga. The catalyst or (in the case of a catalyst formed in situ) its precursor may be introduced before or after the addition of the chloroalkane. If added after the addition of the gas alkane, it may be fed in several portions during the reaction. Alternatively, it may be initially loaded with a force σ ^ The second step of the method of the invention comprises forming in the first step The reaction of vaporized dialkyl gallium with metal gallium to form a trialkyl gallium. A dialkyl metal chloride, an alkyl metal vapor, or a metal tooth gasification will be formed as a by-product. Examples of suitable alkyl metal It is an alkyl aluminum, an alkyl magnesium and an alkyl lithium. More preferably, the alkyl metal is an aluminum alkyl, even more preferably a trialkyl aluminum. The base of the base metal may include a carbon source, preferably To a carbon atom, the alkyl group is preferably the same as the alkyl group of the gas alkane used in the previous step. The methyl group is the most preferred alkyl group; the tridecyl aluminum and the triethyl aluminum system. The most preferred metal alkyl* is preferably in the range of 10,000, more preferably 30 to 500, of the base metal. The metal gallium used in one step is 10 to and most preferably 70 to 4 mole %. The amount is 163598.doc 201249852 and no solvent is required. However, it is preferred to use a hydrocarbon solvent for some reason. Examples of suitable solvents are hexane, calcined, gamma, cinnabar, simmer, simmer, the presence of a solvent during this step, and aliphatic hydrocarbons such as decane and dodecane; saturated alicyclic Hydrocarbons such as cyclohexane and cycloheptane; and aromatic oximes such as toluene, benzene, tris, benzene, ethylbenzene, ethyltoluene and nodules. (4) (4) may be easily separated from the obtained three-chamber gallium t, and more preferably have a difference from the boiling point of the trimethylgallium. Considering the type of di-vaporized dialkyl gallium, the metal alkyl and the optional solvent used, and other factors 'selecting the appropriate reaction temperature' to effectively carry out the reaction is typically at about zero. Up to 200t: preferably about 20. To about 1 50. (:, and more preferably about 30 ° to 120. (:, the reaction is carried out. The temperature of the reactor may increase after the reaction to distill the prepared three bases. The two steps of the method may be the same Performed in the reactor. Alternatively, if desired, the intermediate product alkyl gallium may be distilled, recrystallized, or otherwise purified prior to use in step (ii). The trialkyl gallium obtained by the process of the present invention is suitable. For the preparation of a semiconductor device, for example, a gallium nitride-based semiconductor. The tri-gasified dialkyl gallium obtained by the first step of the method is found to be useful for semiconductor fabrication and for the synthesis of other Ga compound precursors. Also related to a method for preparing dialkyl gallium trichloride. [Examples] Example 1 163598.doc 201249852 Ga (12.00 g, 172.1 mmol) was charged into a 50 ml three-neck reaction flask. MeCl was purged (evacuated and 4 cycles filled with MeCl) and placed in an oil bath. Apply 0.3 bar of MeCl overpressure. Heat the oil bath to 100. (:, and with stirring i2 (4.37) g, 17·2 mmol) lasts 4 The reaction mixture was stirred for π hours at 100 ° C. The obtained reaction mixture had the appearance of a clear amber liquid and had a small amount of unreacted Ga. The obtained dialkyl gallium chloride was at room temperature. The crystals were crystallized from the reaction mixture in about 40 hours. The flask containing the crystalline alkyl gallium trichloride was transferred into a glove box. Dimethylamine (TMAL '3 ml) was added to dissolve the mixture, and the mixture was sucked. After the liquid tube removes unreacted Ga (0·85 g; indicating that the conversion rate of the tri-gasified dialkylgallium formed in the first reaction step is 93%), it is transferred into 100 ml of the oil bath. In a neck flask, residual TMAL (all 37.2 g, 5 16.4 mmol) was added to the flask over 12 minutes. The obtained reaction mixture was distilled to obtain 18 25 g of a transparent product. NMR showed that the product contained About 4 m〇i〇/0 Mel and 96 mol0/〇trimethylgallium. Based on the amount of Ga used in the first step, the yield of crude trimethylgallium is 92% and based on the Ga in the first step. The amount of crude trimethylgallium is 99%. Example 2 Purification with MeCl (about 0.3 bar) 5 〇 ml three-necked flask of Ga (8.〇〇g, 114 7 mm 〇 1), and heated to 5 (rc. Adding > odor (about 0.8 ml '2.52 g, 15.8 mmol) in a syringe over 22 minutes To the burnt plate. 163598.doc -9- 201249852 After all Br2 was added, the temperature of the oil bath was raised to i 〇〇 °c (the internal temperature of the reaction mixture was 951:). After stirring at 10 ° C for 20 hours, 0.73 g of Ga remained unreacted (conversion rate was 91%). Unreacted Ga was removed from the reaction mixture using a pipette. The flask containing the crystallized tri-vaporized dialkyl gallium was transferred to a glove box and placed in an oil bath. A condenser with a receiving flask was attached to the flask and TMAL (24.82 g, 344.1 mmol) was gradually added to the reaction mixture. At the beginning of the addition, the clear clear mixture turned into a grey suspension. The obtained reaction mixture was distilled to obtain 10.36 g of a transparent product (90.2 mmol, a yield of 79% based on Ga used in the reaction with MeCl and a yield of 86.5% based on the reacted Ga) according to the peak in the 1H NMR spectrum. The area has a purity of 99%; MeBr (0.9 mol%) is the main impurity. Example 3 A 100 ml two-necked flask containing Ga (12.00 g, 172.1 mmol) and AlBr3 (12.00 g, 45.0 mmol) was purged with MeCl (about 0.3 bar). After the flask was filled with MeCl, AlBr*3 became a liquid. The reaction vial was quickly rinsed with MeCn every hour to remove gaseous by-products. On the first day, the reaction mixture was stirred at 1 〇〇eC for 5 hours' and residual 〇·5 g Ga remained unreacted. After the mixture was kept at room temperature overnight, the reaction was continued for another 2 hours with MeCl at 1 〇0 °C the next day. A very small amount of Ga (<0·〇5 g) is still visible in the clear liquid product, and the total reaction time at 100 ° C is 7 hours. The flask containing the crystallized tri-vaporized dialkylgallium crystals was transferred into a glove box and placed in an oil bath. The condenser with the receiving flask was connected to the flask at 163598.doc •10·201249852 and the TMAL (37·2 g, 516.4 mmol) was gradually added to the reaction mixture. After the addition of about 10 ml of TMAL, the reaction temperature was raised from 26 ° C to about 80 C ' and the clear clear solution turned into a gray suspension. After adding all TMAL, the oil bath temperature was raised to 120 ° C, and the distillate (boiling point 62 to 72 t) was collected to obtain 17.02 g (i 48.2 mmol, based on Ga used in the first step, 861⁄4 yield) to clarify the transparent product. . When the oil bath temperature was 〇4^, the evaporation was started. According to 1H NMR, the product had a purity of 97%, and 1.5% of the total peak area contributed by MeBr' which corresponds to 4.5 mol% MeBr contamination. The bottom material was stored at room temperature (without stirring) overnight, a small amount of gray solid precipitated and the bottom material was transparent. Comparative Example A 50 ml stainless steel reactor (without agitation) 'seal' was filled with Ga (0.77 g' 11 mmol) and pressurized to 3.9 atm with MeCl. The pressure was 3.8 atm at room temperature (0.4 g, 7.9 mmol MeCl) and heated to 40 °C for 3 days. The reactor contains only Ga metal; no product is formed. This experiment shows that a Lewis acid catalyst is necessary for the reaction of Ga metal with chloroalkane. Without such a catalyst (as in the comparative example of the invention), no reaction will occur. 163598.doc 11