请教下CBS还原剂对产物构型的影响？ 还原羰基过程中，产品的手性是由 R-CBS和S-CBS决定的，还是由原料结构决定的？ 看文献报到的结果有点模糊， file:///C:\Users\ADMINI~1\AppData\Local\Temp\msohtmlclip1\01\clip_image001.png Preparation of (3R,4S)-1-(4-Fluorophenyl)-3-[3-(4-fluorophenyl)-3(S)-hydroxypropyl]-4-(4-benzyloxyphenyl)-2-azetidinone10. To the mixture of dichloromethane (1050 mL) and THF (150 mL) at0 °C were added boranedimethylsulfide (28.7 mL, 0.45 mol) and R-methyloxazaborolidine(12.4 g, 0.04 mol). To this reaction mixture was added keto compound 9 (150 g, 0.30 mol)in dichloromethane and was stirred at the same temperaturefor 3 h. After completion of the reaction, the reaction mixture was quenched with 5% aqueoushydrogen peroxide and theorganic layer was separated. The organic layer was successively washed with hydrochloric acid andbrine solution and thentreated with activated charcoal and filtered. The filtrate was concentrated to give the crudeproduct, which on crystallization in diisopropylether gave 94.1 g (62.5%) of compound 9 as a white solid. 1H NMR (200 MHz,DMSO-d6, δ) 1.6-1.9 (m, 4H), 2.0-2.2 (bs, 1H), 3.0-3.2 (m, 1H), 4.4-4.6 (m, 1H), 4.74 (m, 1H), 5.05 (s, 2H), 6.95-7.9 (m, 17H, Ar); IR: 3492,2922, 2852, 1719 cm-1; MS: m/z 499.3 (M+). file:///C:\Users\ADMINI~1\AppData\Local\Temp\msohtmlclip1\01\clip_image001.png file:///C:\Users\ADMINI~1\AppData\Local\Temp\msohtmlclip1\01\clip_image002.png 查看更多1个回答 . 2人已关注
我想学学英语，做个外贸？ 外贸英语口语900句 －－－论坛参考 https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=741930 第一单元 希望与要求 (1) We’d like to express out desire to establish business relations with you on the basis of equally, mutual benefit and the exchange of needed goods. 我方希望能在平等、互利、互通有无的基础上与贵司建立业务关系 (2) In order to extend our export business to your country, we wish to enter into direct business relations with you. 为了能在贵国拓宽我方的出口业务，我们希望能与你们直接建立业务关系 (3) Our hope is to establish mutually beneficial trading relations between us 我们希望双方能建立互惠的贸易关系 (4) We look forward to a further extension of pleasant business relations 希望我们之间友好的业务关系得到进一步的发展 (5) It’s our hope to continue with considerable business dealing with you 我方希望能够继续同贵方保持大量的业务往来 (6) We look forward to receiving your quotation very soon 我方期待尽快收到贵方的报价 (7) I hope you’ll see from the reduction that we are really doing our utmost 希望贵方能从这一降价中看出我方真的在尽最大的努力 (8) We hope to discuss business with you at your earliest convenience. 我们希望尽早与你方洽谈业务 (9) We wish to express our desire to trade with you in leather shoes. 我方希望能与贵方达成皮鞋贸易 (10) We look forward to your early and trust that through our mutual cooperation we shall be able to conclude this transaction with you in the near future. 我们盼望早日得到你方的答复，并相信通过相互合作，我们不久即可达成这笔交易 (11) I hope we can do business together, and look forward to hearing from you soon 希望我们有合作机会，并静候您的佳音 (12) I hope that we can cooperate happily 希望我们合作愉快 (13) I hope that we can continue our cooperation 希望我们能继续合作 (14) We sincerely hope that this transaction will turn out to the satisfaction of both parties. 我们真心地希望这次交易能使我们双方都能满意 (15) We hope that this market trend will continue 我方希望这种市场趋势能继续发展下去 (16) It is hoped that you would seriously take this matter into consideration and let us have your reply soon 希望你方能认真考虑这件事，并尽快答复我们 (17) We hope that you will deal with our request earnestly 希望能得到贵方的迅速答复 (18) We hope to receive your immediate answer 希望得到贵方的迅速答复 (19) We are looking forward to having your early reply to this matter 希望贵方对这件事能尽早答复 (20) We hope that this dispute can be settled through friendly negotiation without its being submitted for arbitration 我方希望可以通过友好谈判加以解决，而不要仲裁 (21) We look forward to your settlement at an early date. 我方期待着贵方早日解决这一问题 (22) Your early settlement of this case will be appreciated. 如能早日解决这一问题，我方将不胜感激 (23) We hope that you can settle the claim as quickly as possible 希望贵方能尽快解决索赔事宜 (24) We hope that there will be no repetition of this kind of trouble in the future. 希望类似的麻烦将来不再发生 (25) We expect that you will offer us a lower price as soon as possible. 期待贵方能尽快报一个更低的价格 (26) We hope that the matter can be brought to a satisfactory conclusion. 希望此事有一个**的解决 (27) I do hope this undesirable incident will not stand in the way of our future business 我希望这件不愉快的事情不会影响我们今后的贸易 (28) We hope this matter will not affect our good relations in our future dealings. 我希望此事不会影响我们将来业务中的良好关系 (29) I wish that this business will bring benefit to both of us. 希望这笔生意对我们双方都会带来好处 (30) We hope this incident will not bring any harm to our pleasant relations 我们希望此事不会给我们的良好关系带来任何损害 第二单元 产品介绍 (31) This model of typewriter is efficient and durable, economical and practical for middle school students 这个型号的打字机对中学生来说，高效、耐用、经济、实惠 (32) The computer we produced is characterized by its high quality, compact size, energy saving and is also easy to learn and easy to operate. 我们生产的计算机其特点是品质好，体积小，节能，而且易学好用 (33) They are not only as low-priced as the goods of other markers, but they are distinctly superior in the following respects 它们不但和其它厂家的产品一样低廉，而且在以下几个方面有其独特的优越性 (34) You will get a 30% increase in production upon using this machine and also it allows one person to perform the tasks of three people. 一旦使用该机器，你们将会增产30%，而且一个人可以顶3个人使用 (35) This product will pay its own way in a year 该产品一年就可收回成本 (36) This machine will pay back your investment in six months. 该机器半年就可收回投资 (37) The new type of suitcase car designed by our engineers is very ingenious and practical 我方工程师设计的新款行李车非常精巧、实用 (38) This kind of bicycle can be folded in half and handy to carry around, especially useful during traveling and traffic jams. 这种自行车可以折叠，携带方便，在旅行中或交通堵塞时特别有用 (39) The maximum speed of this kind of variable-speed bicycle is 30 km per hour 这种变速车每小时的最大速度是30km (40) These machines have few breakdowns and are easy to maintain because of their simple mechanical structure. 这些机器由于机械的构造简单，所以很少故障，易于保养 (41) Compared with the other brands, this kind of type costs less per mile and wears much longer due to its topnotch rubber 与其它牌子相比，这种轮胎每公司损耗较少，也耐磨一些，因为它是用一种流橡胶做成的 (42) This kind of type is characteristic of nonskid stops on wet roads 这种轮胎的特点是在潮湿的路面上不打滑 (43) This material has a durable and easy to clean surface. 这种材料的表面耐用并容易清洗 (44) This kind of air conditioning system is practical and economical for the needs of your company 这种空调系统实用、经济、能满足贵公司的需要 (45) Our products are of superb quality as well as the typical oriental make-up 我方产品，品质优良，具有典型的东方特色 (46) Our silk garments are made of super pre silk materials and by traditional silks 我们的丝绸服装是用传统工艺做成的，采用的是高档真丝面料 (47) The garments are magnificent and tasteful and have a long enjoyed great fame both at home and abroad. 这些服装华丽、高雅、驰名中外，久享盛誉 (48) As our typewriters are made of light and hard alloy, they are both portable and durable 我们的手提式打字机是用轻质硬合金制造的，故携带方便，经久耐用 (49) The hand bags we quoted are all made of the best leather and of various kinds of styles and colors in order to meet the requirements of all walks of life in your country 我们所提的手提包均用最好的皮革制造，式样、颜色齐全，以适合贵国各阶层人士的需求 (50) As our product has all the features you need and is 20% cheaper compared with that of Japanese make, I strongly recommend it to you 我们的产品具备了您所需要的各项特色，而且比日本产品便宜20%，所以我们向您极力推荐。 (51) Vacuum cleaners of this brand are competitive in the international market and are the best-selling products of their Kind. 这种牌子的 吸尘器 在国际市场上颇具竞争力，是同类产品中最畅销的 (52) “Forever” multiple speed racing bicycles are sure to be salable in your market 永久牌变速跑车在你们的市场上一定很畅销 (53) Owing to its superior quality and reasonable price, our silk has met with a warm reception and quick sale in most European countries 我们的丝绸品质优良，价格公道，深受大多数欧洲国家的欢迎，非常畅销。 (54) We feel that our product is the best kind in Asia and we can very well compete against Japan in price 我们认为我们的产品在亚洲是最好的，在价格上完全可以与日本竞争 (55) Our goods are greatly appreciated in other markets similar to your own 我们的产品在其它市场同在贵方市场一样受到欢迎 (56) By virtue of this superior quality, this product is often sold out in many areas. 我们的产品因其优秀的品质，在很多地区经常脱销 (57) Our products are superior in quality and moderate in price and are sure to be saleable in your market 我们的产品品质优秀，价格适中，在贵方市场上一定很畅销 (58) These items are most salable in our market 在我方市场上，这些产品是最畅销的。 (59) There has been a steady demand in our market for this kind of toy 在我们的市场上，这种玩具的需求一直很稳定 (60) We have the pleasure in recommending you the goods similar to the samples you sent 我们很高兴地向你们推荐类同于贵方所提供之样品的样品 Unit 3 业务范围介绍 Part One (61) We wish to introduce ourselves to you as a sate-owned corporation dealing exclusively in light industrial goods. 我们是一家国营公司，专营轻工产品 (62) We are introducing ourselves as one of the lading exporters of the same line of business 我们是同一业务范围内的主要出口商之一 (63) We have the pleasure of introducing ourselves to you as a state corporation specializing in the export of canned goods. 我们很荣幸地向你们自我介绍，我们专营出口罐头食品的一家国营公司 (64) We introduce ourselves as dealers in bicycles and spare parts. We have been in this line for over two decades. 我们是自行车和零部件的经销商，我们在这一行业已经做了20 多年了。 (65) Our corporation is specialized in handling the export business of textiles 我们公司专营纺织品出口业务 (66) The main products our corporation deals in are electrical appliances. 我们公司经营的主要产品是电器 (67) Our company is mainly engaged in agricultural products. 我公司主要经营农产品 (68) We specialize in the export of table-cloths. 我们专营餐布的出口业务 (69) Our company mainly deals with the export business of silk goods. 我公司主要经营丝织品的出口业务 (70) Our specialization is the exportation of Chinese silk garments 我们专门经营中国丝绸服装的出口业务 (71) We are engaged in the import and export of machinery. 我们经营机械进出口业务 (72) We are now doing a large import business in fruits from Southeast Asia. 我们的业务是大批量进口东南亚的果品 (73) We specialize in handling clocks and watches of all sorts. 我们专门经营各种类型的钟表 (74) We also take on a variety of silk piece goods 我们也经营各种绸缎的生意 (75) Our activities cover a wide range of commodities, such as ties, belts and shirts. 我们经营的商品范围多样，有领带、皮带、衬衫等。 Part Two (76) We are in a very good position to supply most grades of canned fish at competitive prices and for good delivery 我们完全有能力以最具有竞争性的价格提供各种鱼类罐头 (77) We are in a position to accept orders against customers samples specifying design, specifications and packaging requirements. 我们可以按照客户所提供的样品并根据其所要求的式样、规格、包装要求等接受订单 (78) We are not exporting straw and willow products, embroideries, porcelain wares, jade carvings, antiques, Chinese paintings, silk flowers and various kinds of toys and gifts. 我们做草柳制品，刺绣制品，陶瓷，玉雕，古玩，国画，绢花和各种各样的玩具和礼物的出口业务 (79) Our corporation is a major producer of technically advanced machinery and chemicals for industry and agriculture. 我们公司主要生产用于工业和农业的具有先进技术的机械和化工产品 (80) Electronic products fall within the scope of our business activities 电子产品属于我们的业务经营范围 (81) We also do export business of hand made woven articles. 我们也做手工编制物品的出口业务 (82) We have been engaged in the glass business with many Asian countries for many years 多年来我们一直在和许多亚洲国家做玻璃的业务 (83) Our company is mainly in the line of exporting Chinese art objects to European markets. 我们公司专做向欧洲市场出口中国 工艺品 的生意 (84) We also do import and export business in chemicals and agricultural products 我公司还经营化学产品和家产品进出口的业务 (85) We have been importing and exporting all kinds of metals and minerals for 30 years and have many customers and friends in over 80 countries and regions (86) Our corporation is a group enterprise integrating scientific research, business, production and service. 我们的公司是一家企业集团，集科研、业务、生产和售后服务为一体 (87) As a joint venture, our corporation has won a prominent position in the fields of home electronics, computers and telecommunications in China 作为一家合资企业，在中国境内，我们公司在家用电器、计算器、电讯等领域处领先地位 (88) We are prepared to accept orders for goods with customers’ own trade marks or brand names 我们可以按照客户所指定的商品的商标和牌号接受订单 (89) We have been handling leather shoes and gloves for more than 20 years 我们经营皮鞋和手套已经有20多年了。 (90) We have been engaged for two decades in the manufacture of such equipment. 我们从事这类设备的制造已20年了。 查看更多6个回答 . 2人已关注
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