Smith 2 Group

Braddock Smith Group, Inc., NBC Products and Services Handbook. Great Falls, VA, May 2004. Available online at http //www.nbcindustrygroup.com/... 

The described procedure has been widely used by Smith III and coworkers [250] in the efficient total synthesis of natural products containing extended 1,3-hydroxylated chains. This architecture is often found as a structural element in polyene macrolide antibiotics [251] such as mycotoxin A and B, dermostatin, and roxaticin. The Smith group used the above-mentioned approach (e. g., as five-component coupling) for the synthesis of the pseudo-C2-symmetric trisacetonide (+)-2-471 [252], which was employed by Schreiber and coworkers [253] within the synthesis of (+)-mycotoxin A (2-470a) (Scheme 2.108). Thus, lithiation of 2.5 equiv. dithiane 2-462b followed by treat-... 

As a result of the excellent precedent from the Takeda and Smith groups, we targeted vinylsilane 136 as a key intermediate in a Brook rearrangement/conjugate... 

The Smith group has also developed the methodology for making high precision calculations for small systems without invoking the Born-Oppenheimer approximation and have made calculations for two-electron atomic ions, small muonic molecules, and potentials of the screened Coulomb form. Their method for determining nonlinear parameters is now referred to as random tempering.169... 

The Smith group has also achieved the total synthesis of rapamycin (2) and demethoxyrapamycin (Fig. 6). Their total synthesis of 2 features aldol reaction of acetylpipecolic acid and the C10-C20 segment, esterification with the C21-C42 segment, and final Stille macrocyclization at the C20 and C21 positions. 

Our final example, taken from the last step in a synthesis of Cyclindrocyclo-phane A by Hoye and co-workers [Scheme 4.109], required the cleavage of the four phenolic methyl groups in 109.1.Fusion with excess methylmagnesium iodide at 160 ""C under vacuum afforded Cydindrocyclophane A in 60% yield. No other by-products were observed in which both secondary benzylic alcohols survived unscathed. The same quadruple demethylation was accomplished in 60% yield by the Smith group using benzenethiol and potassium carbonate at 215... 

Combined structure problems provided by the Smith group at Notre Dame University. 

The Smith group at the University of Notre Dame has a number of combined problems ... 

Photo Researcher Bill Smith Group Text Researcher Pablo D Stair Text Designer Parallelogram Graphics... 

In 2013, the Smith group reported asymmetric a-amination through an NHC-catalyzed redox reaction of a-aroyloxyaldehydes with A/-aryl-AI-aroyldi-azenes to form a-hydrazino esters with high enantioselectivity (up to 99% ee). The hydrazide products are readily converted into enantioen-riched A -aryl amino esters through Sml2-mediated N—N bond cleavage (Scheme 7.83). 

FIGURE 36.2 Issues affecting design for hospitals in the future. (Adapted from The Hospital of the Future, Smith Group, 2001.)... 

Recently, the asymmetric formal [2 + 2] cycloaddition of allqrlaiylketenes with both electron-deficient benzaldehydes and 2- and 4-pyridinecarbox-aldehydes was reported by the Smith group, providing p-lactones 168 in good yields and enantioselectivities (Scheme 20.70). 

BMW, Ford, GKN, Honda, Nissan, Peugeot and Toyota. In the aerospace and defence sector, BAE Systems, Rolls-Royce, Messier-Bugatti-Dowty and Smiths Group play an important role. 

Text Designer RHDG Riezebos Hoizbaur Photo Researcher The Biii Smith Group/... 

Text Designer Jeanne Calabrese Photo Researcher Scott Rosen, Bill Smith Group... 

Since the late 1990s, the Smith group developed and utilized the Petasis-Ferrier union/rearrangement for the synthesis of 2,6-c -tetrahydropyran-4-ones. This... 

In 2001 and 2002, the Smith group first disclosed the total synthesis of (+)-zampanolide [164] and (-n)-dactylolide [165], respectively. The synthetic strategy of (-i-)-zampanolide relied on the stereoselective construction of the 2,6-cjT-tetrahydropyran unit via the Petasis-Ferrier rearrangement and Horner-Wadsworth-Emmons macrocyclization at the C(2)-C(3) junction (Scheme 2.47). 

Floreancig and co-workers communicated the synthesis of (+)-dactylolide in 2005. The key step of Floreancig s synthesis involved an asymmetric vinylogous Mu-kaiyama-aldol reaction and an intramolecular Prins cyclization of the acetal bearing substrate. The macrocyclization of the synthesis was achieved by Honer-Wadsworth-Emmons olefination as demonstrated by the Smith group in the first total synthesis of (+)-zampanolide (Schemes 2.55, 2.56). 

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