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Aldrich Chemical Co. congratulates Professor K. Barry Sharpless of The Scripps Research Institute for receiving a share of the 2001 Nobel Prize in Chemistry for his practical research on "chirally catalyzed oxidation reactions". The laureate's work has been adapted to a number of industrial syntheses of antibiotics, antidepressants, anti-inflammatory drugs, and heart medicines. Professor Sharpless has successfully developed three catalytic techniques to yield enantiomerically pure products. The first, the Sharpless asymmetric epoxidation (AE), 1 transforms allylic alcohols into epoxy alcohols using a novel titanium-based catalyst. The second, the Sharpless asymmetric dihydroxylation (AD), 2 uses an osmium-based catalyst to asymmetrically dihydroxylate olefins. The wide acceptance of this methodology has prompted researchers to develop a new class of ligands,(DHQD)2AQN and (DHQ)2AQN, in order to expand the scope of the reaction. 3 These two are useful complements to the ligands we already offer: (DHQD)2PYR/ (DHQ)2PYR and (DHQD)2PHAL/(DHQ)2PHAL. 4 The success of AD led the way for Sharpless's third method, the Sharpless asymmetric aminohydroxylation (AA). 5 The key stoichiometric reagent in this method is the oxidant Chloramine-T, which is a nitrogen analog of sodium hypochlorite and formally acts as a reservoir of "sulfonyl nitrene". The transformation is illustrated by the synthesis of a Taxol ® side chain from methyl cinnamate. Along with asymmetric induction, the chiral ligand provides dramatic enhancements in regioselectivity as well as suppression of the path(s) responsible for the formation of the diol by-product. All products listed here are sold under license from Rhodia ChiRex. Taxol is a registered trademark of Bristol-Myers Squibb. References: (1) Katsuki, T.; Sharpless, K.B. J. Am. Chem. Soc. 1980, 102, 5974. (2)(a) Jacobsen, E.N.; Markó, I. Mungall, W.S.; Schröder, G.; Sharpless, K.B. ibid. 1988, 110, 1968. (b) Kolb, H.C.; VanNieuwenhze, M.S.; Sharpless, K.B. Chem. Rev. 1994, 94, 2483. (3) Becker, H.; Sharpless, K.B. Angew. Chem., Int. Ed. Engl. 1996, 35, 448. (4) Becker, H.; King, S.B.; Taniguchi, M.; Vanhessche, K.P.M.; Sharpless, K.B. J. Org. Chem. 1995, 60, 3940. (5) Li, G.; Chang, H.-T.; Sharpless, K.B. Angew. Chem., Int. Ed. Engl. 1996, 35, 451. Products: Sharpless Asymmetric Dihydroxylation Sharpless Asymmetric Aminohydroxylation 45,671-3(DHQD)2AQN, 95% 45,670-5 (DHQ)2AQN, 95% 39,275-8 AD-mix-α 39,276-6 AD-mix-β 39,272-3 (DHQ)2PHAL, 95+% 39,273-1 (DHQD)2PHAL, 95+% 41,897-8 (DHQ)2PYR, 97% 41,895-1 (DHQD)2PYR, 97% 40,286-9 Chloramine-T trihydrate, 98%, A.C.S. reagent 85,731-9 Chloramine-T hydrate, 98% For competitive quotes on larger quantities contact www.sigma-aldrich.com/safc.
Equipment for Air-Sensitive Chemistry Serrated rubber septa Closure has a turnover flange molded to grip outside of container neck, promoting a double seal in conjunction with annular serrations on a hollow plug. Annular serrations depress themselves against the inside wall of the bottle neck, making each serration a suction sealing point. Fits container neck i.d. For use White rubber Red rubber Blue rubber (mm) with: Cat. No. Cat. No. Cat. No. 8.0 10/30 Z51,217-6 Z51,216-8 Z51,264-8 12.5 14/20 Z51,212-5 Z51,211-7 Z51,267-2 16.0 Sure/Seal Z51,219-2 Z51,218-4 Z51,269-9 17.5 19/22 Z51,221-4 Z51,220-6 Z51,270-2 20.5 24/40 Z51,214-1 Z51,213-3 Z51,272-9 25.5 29/42 Z51,223-0 Z51,222-2 Z51,275-3 ALDRICH ATMOSBAGS The Aldrich AtmosBag is a 0.003in. gauge PE bag that can be sealed, purged, and inflated with an appropriate inert gas, creating a portable, convenient, and inexpensive "glove box" for handling air-and moisturesensitive, as well as toxic*, materials. Other applications include dust-free operations, controlled atmosphere habitat, and, for the sterile ethylene oxide-treated AtmosBag, immunological and microbiological studies. Small AtmosBags have one inlet per side. Includes instructions. Uninflated Inflated dim. (in.) vol. Non-sterile Sterile Size Opening W x L (ft 3 ) (L) Cat. No. Cat. No. Two-hand AtmosBags S 1227 x 30 1.74 350 Z11,283-6 Z11,837-0 M 24 39 x 48 39.84 280 Z11,282-8 Z11,836-2 L 36 51 x 58 18.52 520 Z10,608-9 Z11,835-4 Four-hand AtmosBag 30 45 x 58 – – Z10,840-5 AtmosBag accessories PE bench-top bases Rigid, Fin. thick. Keeps AtmosBag in place. Fits inside respective bag. S 11 x 16in. Z11,286-0 M 20 x 16in. Z11,285-2 L 24 x 34Fin. Z10,691-7 Mini-size Benchrack Includes base and Min. diam. lattice rod sections. No. of No. of Base dim. positions rods (in.) Cat. No. 4 8 19 x 8 Z22,565-7 SIlicone Serrated Septa (Shown above at right) are excellent for high-heat and sterile applications. See the Aldrich Handbook for a listing of these products. Two-hand AtmosBag shown here with PE benchtop base and Benchrack lattice system (see below). *CAUTION: Always handle toxic materials in a hood or other controlled system to prevent and protect against exposure in case of leakage. All products made of PE may tear, break, or puncture. To assure that air-sensitive materials do not become exposed to air, follow instructions on package; also, test and monitor AtmosBag for leaks before and during use.
Page 1 and 2: DEDICATED TO PROFESSOR H. C. BROWN
Page 3 and 4: Aldrich Chemical Co., Inc. 1001 Wes
Page 5 and 6: Boron-Based Reducing Agents for the
Page 7 and 8: Figure 3. Stoichiometric Boron-Base
Page 9 and 10: orane reductions 29,30 of 1,4-diphe
Page 11 and 12: α-Hydroxy Acetals R Reduction Cond
Page 13 and 14: and 5 provided moderate ee’s in t
Page 15 and 16: Other reductions using 14, 64c,d 16
Page 17 and 18: Masuda, H.; Ito, K.; Hirao, A.; Nak
Page 19 and 20: The synthesis of biaryl compounds v
Page 21 and 22: 52,396-8 [87199-18-6] 3-Hydroxyphen
Page 23: Josiphos is a family of chiral phos
Page 27 and 28: Equipment Equipment for Air-Sensiti
Page 29 and 30: Equipment for Air-Sensitive Chemist
Page 31 and 32: Glassware for Air-Sensitive Chemist
Page 33 and 34: Pinane-Based Versatile “Allyl”b
Page 35 and 36: B-O bond. 15 The mechanism involves
Page 37 and 38: Scheme 4. Tartrate Ester Auxiliary
Page 39 and 40: eagent with aldehydes at low temper
Page 41 and 42: from 2- and 3-carene turned out to
Page 43 and 44: Scheme 22. Application of Crotylbor
Page 45: Abstr. 1968, 68, 29743j. (11) Refer
Page 48 and 49: New! New! Transition-metal-catalyze
Page 50 and 51: Let us be your preferred supplier o
Page 52 and 53: These distillation heads are design
Page 54 and 55: Advanced Organic Chemistry: Reactio
Page 56: ALDRICH CHEMICAL COMPANY, INC. P.O.

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