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Asymmetric Sharpless

Sharpless Asymmetric Dihydroxylation (AD) - Ligand pair are really diastereomers ... [Pg.14]

Fig. 8. Use of Sharpless asymmetric epoxidation for the preparation of an intermediate in the synthesis of FK-506 (105), where represents the chiral... Fig. 8. Use of Sharpless asymmetric epoxidation for the preparation of an intermediate in the synthesis of FK-506 (105), where represents the chiral...
SHARPLESS Asymmetric Oihydroxylation Enantioselecthfe syn dihyroxylation of olefins using AO-mn-p formed from phthalazine-... [Pg.344]

Figure 1. Stereofacial selectivity rule for the Sharpless asymmetric epoxidation. Figure 1. Stereofacial selectivity rule for the Sharpless asymmetric epoxidation.
The essential features of the Masamune-Sharpless hexose synthesis strategy are outlined in a general way in Scheme 4. The strategy is based on the reiterative- application of a two-carbon extension cycle. One cycle comprises the following four key transformations (I) homologation of an aldehyde to an allylic alcohol (II) Sharpless asymmetric epoxidation of the allylic alcohol ... [Pg.298]

The emergence of the powerful Sharpless asymmetric epoxida-tion (SAE) reaction in the 1980s has stimulated major advances in both academic and industrial organic synthesis.14 Through the action of an enantiomerically pure titanium/tartrate complex, a myriad of achiral and chiral allylic alcohols can be epoxidized with exceptional stereoselectivities (see Chapter 19 for a more detailed discussion). Interest in the SAE as a tool for industrial organic synthesis grew substantially after Sharpless et al. discovered that the asymmetric epoxidation process can be conducted with catalytic amounts of the enantiomerically pure titanium/tartrate complex simply by adding molecular sieves to the epoxidation reaction mix-... [Pg.345]

Scheme 3. The ARCO Chemical Company s commercial synthesis of the glycidols using the Sharpless asymmetric epoxidatlon reaction. Scheme 3. The ARCO Chemical Company s commercial synthesis of the glycidols using the Sharpless asymmetric epoxidatlon reaction.
Scheme 4. The Sharpless asymmetric epoxidation in the J.T. Baker Company s commercial synthesis of (7/ ,8S)-disparlure (15). Scheme 4. The Sharpless asymmetric epoxidation in the J.T. Baker Company s commercial synthesis of (7/ ,8S)-disparlure (15).
The construction of key intermediate 18 can be conducted along similar lines. Sharpless asymmetric epoxidation of allylic alcohol 22 using (+)-DET furnishes epoxy alcohol 52b (Scheme 11). Subjection of the latter substance to the same six-step reaction sequence as that leading to 54a provides allylic alcohol 54b and sets the stage for a second SAE reaction. With (+)-DET as the... [Pg.436]

A noteworthy feature of the Sharpless Asymmetric Epoxidation (SAE) is that kinetic resolution of racemic mixtures of chiral secondary allylic alcohols can be achieved, because the chiral catalyst reacts much faster with one enantiomer than with the other. A mixture of resolved product and resolved starting material results which can usually be separated chromatographically. Unfortunately, for reasons that are not yet fully understood, the AD is much less effective at kinetic resolution than the SAE. [Pg.686]

Jacobsen epoxidation 359 -, Katsuki epoxidation 361 -, Mukaiyama-aldol reaction 367 f. -, oxime ether reduction 363 -, Sharpless asymmetric dihydroxyla-tion 361... [Pg.790]

SAE reaction see Sharpless asymmetric epoxidation Saegusa oxidation 390 samarium diiodide 496, 633, 638 saponification 49, 207 sativene 382 f. [Pg.796]

DIPT diisopropyl tartrate SAE Sharpless Asymmetric Epoxidation... [Pg.809]

The development of Sharpless asymmetric epoxidation (SAE) of allylic alcohols in 1980 constitutes a breakthrough in asymmetric synthesis, and to date this method remains the most widely applied asymmetric epoxidation technique [34, 44]. A wide range of substrates can be used in the reaction ( ) -allylic alcohols generally give high enantioselectivity, whereas the reaction is more substrate-dependent with (Z)-allylic alcohols [34]. [Pg.322]


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Alkenes Sharpless asymmetric

Alkenes Sharpless asymmetric dihydroxylation

Alkenes Sharpless asymmetric epoxidation

Alkenes Sharpless asymmetric hydroxylation reactions

Allylic alcohols Sharpless asymmetric

Allylic alcohols Sharpless asymmetric epoxidation

Allylic alcohols Sharpless-Katsuki asymmetric epoxidation

Amides Sharpless asymmetric

Asymmetric Sharpless ligands

Asymmetric dihydroxylation Sharpless’ method

Asymmetric epoxidation Sharpless titanium

Asymmetric synthesis Sharpless-Katsuki epoxidation

Catalytic Asymmetric Synthesis Sharpless Oxidations of Allylic alcohols

Chiral ligands, Sharpless asymmetric

Chiral ligands, Sharpless asymmetric hydroxylation reactions

Chlorobenzoate, Sharpless asymmetric

Cinchona alkaloids, Sharpless asymmetric

Dihydroquinidine, Sharpless asymmetric

Dihydroquinine, Sharpless asymmetric

Dimerization effects, Sharpless asymmetric

Dimerization effects, Sharpless asymmetric dihydroxylation

Enantioselectivity Sharpless asymmetric

Enantioselectivity in Sharpless asymmetric epoxidatio

Epoxides Sharpless-Katsuki asymmetric synthesi

Homoallylic alcohols, Sharpless asymmetric

In Sharpless asymmetric

In Sharpless asymmetric epoxidation

Ketones Sharpless asymmetric

Nitrogen source, Sharpless asymmetric

Os-catalyzed asymmetric dihydroxylation (Sharpless reaction)

Oxidation Sharpless-Katsuki asymmetric epoxidation

Oxidation sharpless asymmetric

Propranolol Sharpless asymmetric epoxidation

Reactions Sharpless asymmetric dihydroxylation

SHARPLESS Asymmetric dihydroxylation

SHARPLESS Asymmetric epoxidation

Selenoxides Sharpless asymmetric

Sharpless

Sharpless asymmetric 3, 3] sigmatropic

Sharpless asymmetric amino

Sharpless asymmetric amino hydroxylation

Sharpless asymmetric aminohydroxylation

Sharpless asymmetric aminohydroxylations

Sharpless asymmetric dihydroxylatio

Sharpless asymmetric dihydroxylation Catalytic cycle

Sharpless asymmetric dihydroxylation Diastereoselectivity

Sharpless asymmetric dihydroxylation Regioselectivity

Sharpless asymmetric dihydroxylation Synthesis

Sharpless asymmetric dihydroxylations

Sharpless asymmetric epoxidatio of allylic alcohol

Sharpless asymmetric epoxidation Catalyst structure

Sharpless asymmetric epoxidation Claisen

Sharpless asymmetric epoxidation Kinetic resolution using

Sharpless asymmetric epoxidation Propranolol synthesis

Sharpless asymmetric epoxidation Synthesis

Sharpless asymmetric epoxidation anionic oxy-Cope

Sharpless asymmetric epoxidation dihydroxylation

Sharpless asymmetric epoxidation directed epoxidations

Sharpless asymmetric epoxidation examples

Sharpless asymmetric epoxidation natural products synthesis

Sharpless asymmetric epoxidation of allylic alcohol

Sharpless asymmetric epoxidation of allylic amine oxides

Sharpless asymmetric epoxidation of allylic ethers

Sharpless asymmetric epoxidation of allylic selenoxides

Sharpless asymmetric epoxidation of allylic sulfonium ylides

Sharpless asymmetric epoxidation of allylic sulfoxides

Sharpless asymmetric epoxidation of ammonium ylides

Sharpless asymmetric epoxidation of ester silyl enol ethers

Sharpless asymmetric epoxidation of unsaturated iminium ions

Sharpless asymmetric epoxidation oxy-Cope

Sharpless asymmetric epoxidation process

Sharpless asymmetric epoxidation reaction

Sharpless asymmetric epoxidation stereochemistry

Sharpless asymmetric epoxidation stereoselectivity

Sharpless asymmetric epoxidation substituent effects

Sharpless asymmetric epoxidation titanium catalysts

Sharpless asymmetric epoxidations

Sharpless asymmetric hydroxylation

Sharpless asymmetric propranolol

Sharpless asymmetric rearrangement

Sharpless asymmetric synthesis

Sharpless asymmetric system

Sharpless catalytic asymmetric aminohydroxylation

Sharpless kinetic asymmetric epoxidation

Sharpless-Katsuki asymmetric

Sharpless-Katsuki asymmetric epoxidation

Sharpless-Katsuki asymmetric epoxidation Mechanism

Sharpless-Katsuki asymmetric epoxidation Synthetic Utility

Subject Sharpless asymmetric hydroxylation

Synthesis of the Side Chain by Sharpless Asymmetric Aminohydroxylation

The Sharpless Asymmetric Epoxidation

Titanium complexes (Sharpless Ti tartrate asymmetric epoxidation catalyst)

Use of Sharpless asymmetric

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