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Upstream product

• 6117-91-5 (E/Z)-2-buten-1-ol 
• 1099-45-2 ethyl (triphenylphosphoranylidene)acetate 
• 867-13-0 diethoxyphosphoryl-acetic acid ethyl ester 
• 123-73-9 crotonaldehyde 
• 20316-32-9 ethyl 3-hydroxy-5-methyl-4-pentenoate 
• 74-88-4 methyl iodide 
• 598-32-3 2-hydroxy-3-butene 
• 127492-03-9 1-(phenylsulfinyl)-2,2,2-triethoxyethane 

Relevant academic research and scientific papers

OMS-2 for aerobic, catalytic, one-pot alcohol oxidation-wittig reactions: Efficient access to α,β-unsaturated esters

Manganese oxide octahedral molecular sieve (OMS) materials with well-defined pores have been extensively studied over two decades due to their intriguing chemical and physical properties. OMS-2, the synthetic cryptomelane form of manganese oxide, was synthesized by a modified reflux method and was found to be highly active for obtaining α,β-unsaturated esters (up to 95 % yield and with high diastereoselectivities) from a variety of benzyl, heteroaryl, allyl and alkyl alcohols via one-pot alcohol oxidation-Wittig reaction. The transformation utilizes air as the stoichiometric oxidant, and the inexpensive catalyst can be recovered and reused. Filter and use again! Porous manganese oxide molecular sieve based catalysts were found to efficiently promote the oxidation of a variety of alcohols to the aldehydes, which reacted insitu with stabilized Wittig reagent, providing almost exclusively E-α,β-unsaturated esters in good to excellent yields. The heterogeneous catalyst used was made from inexpensive starting materials, and the recovered catalyst was found to be reusable with a modest loss in activity.

N-Alkenyl Nitrone Dipolar Cycloaddition Routes to Piperidines and Indolizines. Part 6. Allylic Stereocontrol in the Intramolecular Cyclisation of Monosubstituted Nitrones

The intarmolecular, thermal dipolar cycloadditions of the (Z)-N-alk-4-enyl nitrones 18-21, 34 and 36 bearing a single, allylic substituent were investigated.Certain alkoxy substituted nitrones 18-21 showed a remarkable preference for the formation of axially substituted isoxazolidines 22a-24a, whereas the propyl and trifluoromethyl substituted nitrones 35 and 34 gave the equatorially substituted cycloadducts 37 and 36a respectively, consistent with the involvement of 'chair-like' transition states 38.

One-Flask, Regiospecific Conversions of Allylic Alcohols into Two-Carbon-Extended, Conjugated Dienoate Esters. Use of a New Sulfinyl Orthoester

Sixteen differently substituted primary and secondary allylic alcohols are shown to react with sulfinyl orthoacetate 1 at 100 deg C sequentially via a sigmatropic rearrangement and then a β-elimination of benzenesulfenic acid to form conjugated dienoate esters 5-13 in 45-95percent yields.This one-flask, intramolecular carbon-carbon bond-forming process represents a simple and convenient method for regiospecific γ-attachment of a two-carbon (ethoxycarbonyl)methylene unit via the synthetic equivalent of an SN2' process.Two examples are given in which rationally designed dienoates 20 and 24, prepared via this one-flask process and carrying a pendant alkene unit, undergo intramolecular 2+4 cycloaddition producing bicyclic cyclohexenes 21 and 25.

Asymmetric total synthesis of an a-ring precursor to hormonally active 1α,25-dihydroxyvitamin D3

A new sulfinyl orthoester has been designed and used effectively in one-flask syntheses of dienoate esters from allylic alcohols; this new method as well as a highly stereocontrolled [2 + 4]-cycloaddition are applied to synthesis of 1α,25-dihydroxyvitamin D3.

HORNER-WADSWORTH-EMMONS REACTION: USE OF LITHIUM CHLORIDE AND AN AMINE FOR BASE-SENSITIVE COMPOUNDS

A mild olefination procedure, utilizing LiCl and an amine, has been developed for use with base-sensitive aldehydes and phosphonates.