68973-05-7

Upstream product

• 68972-93-0 (E)-1,4-bis(benzyloxy)-2-butene 
• 68972-96-3 (Z)-1,4-dibenzyloxy-2-butene 
• 100-39-0 benzyl bromide 
• 17401-06-8 (2S,3S)-1,4-bis(benzyloxy)-2,3-butanediol 
• 100-51-6 benzyl alcohol 

Downstream Products

• 136258-99-6 (2R,3S)-1,4-Bis-benzyloxy-3-iodo-butan-2-ol 
• 1271145-22-2 (2R*,3S*)-2,3-bis(benzyloxymethyl)-1,4-dioxane 
• 162369-37-1 2,3-bis((benzyloxy)methyl)thiirane 
• 68972-96-3 (Z)-1,4-dibenzyloxy-2-butene 
• 1228035-00-4 meso-1,4-bis(benzyloxy)-2,3-difluorobutane 
• 200636-22-2 (2R,3S)-1,4-dibenzyloxy-3-(3-pivaloyloxypropoxy)butan-2-ol 

Relevant academic research and scientific papers

The synthesis of the 2, 3-difluorobutan-1, 4-diol diastereomers

The diastereoselective synthesis of fluorinated building blocks that contain chiral fluorine substituents is of interest. Here we describe optimisation efforts in the synthesis of anti-2, 3-difluorobutane-1, 4-diol, as well as the synthesis of the corresponding syn-diastereomer. Both targets were synthesised using an epoxide opening strategy.

Facile synthesis of chiral 1,2-chlorohydrins via the ring-opening of meso-epoxides catalyzed by chiral phosphine oxides

The facile synthesis of chiral 1,2-chlorohydrins via the enantioselective ring-opening of meso-epoxides with silicon tetrachloride in the presence of a chiral phosphine oxide was accomplished. The chiral 1,2-chlorohydrins were also obtained from the corresponding cis-alkenes in one-pot without significant loss in the selectivity, thereby permitting easy access to the 1,2-chlorohydrins from cis-alkenes with good yields and enantioselectivities.

Stereoselective synthesis of trisubstituted olefins by a directed allylic substitution strategy

New methodology for the stereoselective synthesis of trisubstituted olefins is presented. The use of ortho-diphenylphosphanyl benzoate (o-DPPB) as a directing leaving group for copper-mediated allylic substitution with Grignard reagents allowed for the stereoselective construction of a wide range of E olefins, without the need for an adjacent electron-withdrawing group. Our modular three-step approach toward trisubstituted alkenes commenced with geminal α-methylene aldehydes. Addition of an organometallic reagent and introduction of the o-DPPB group by esterification was followed by the o-DPPB-directed copper-mediated allylic substitution with a Grignard reagent to furnish stereodefined trisubstituted olefins. Additionally, incorporation of a stereocenter from the chiral pool allowed the preparation of an enantiomerically pure olefin that bore three alkyl substituents in high E/Z selectivity.

Synthesis of 5-thiodidehydropyranylcytosine derivatives as potential anti-HIV agents

As a part of our ongoing efforts to identify new anti-HIV agents, a 5′-thiopyrano-nucleoside derivative 4, designed based on 4′-thioD4C 1 and cyclohexenylnucleoside 3, was synthesized. The dihydrothiopyran skeleton of 4 was constructed by the ring closing metathesis of 21 which was synthesized from but-2-yne-1,4-diol. After converting the protecting group from MOM to TBS followed by oxidation, a Pummerer-type thioglycosylation reaction of 24 with persilylated uracil gave the desired 5-thiodihydrothiopyranyluracils 25 and 26 as a mixture of anomers. The conversion of 25 to a cytosine derivative and subsequent deprotection gave a 5-thiodidehydropyranosylcytosine derivative 4 in good yield. The anti-HIV activity of 4 was also evaluated.

Synthesis of 3,4-Ethylenedioxythiophene (EDOT) from (Z)-but-2-ene-1,4-diol or but-2-yne-1,4-diol

3,4-Ethylenedioxythiophene (EDOT) was synthesized from commercially available (Z)-but-2-ene-1,4-diol or but-2-yne-1,4-diol using epoxidation, etherification, and thiophene formation. The Japan Institute of Heterocyclic Chemistry.

New methodology for the conversion of epoxides to alkenes

Epoxides have been transformed in good yields to alkenes by a process involving (i) ring-opening of the epoxide with 2-mercaptobenzothiazole, (ii) oxidation of the derived ss-hydroxy thioethers to the corresponding sulfones, and (iii) thermal or base-promoted fragmentation of these sulfones to alkenes. The stereochemistry of the starting epoxide is transfer-red faithfully to the alkene product, because of the SN2 epoxide ring-opening reactions and the antiperiplanar SO2 elimination reaction of the ss- alkoxysulfinate intermediates. This methodology may form the basis of a new protecting group strategy for alkenes.

Diastereomerically and enantiomerically pure 2,3-disubstituted pyrrolidines from 2,3-aziridin-1-ols using a sulfoxonium ylide: A one-carbon homologative relay ring expansion

An ylide-based aza-Payne rearrangement of 2,3-aziridin-1-ols leads to an efficient process for the preparation of pyrrolidines. The aza-Payne rearrangement under basic reaction conditions favors the formation of epoxy amines. Subsequent nucleophilic attack of the epoxide by the ylide yields a bis-anion, which upon a 5-exo-tet ring-closure yields the desired pyrrolidine, thus completing the relay of the three-membered to the five-membered nitrogen-containing ring system. This process takes place with complete transfer of stereochemical fidelity and can be applied to sterically hindered aziridinols.

Silver(I) oxide mediated highly selective monotosylation of symmetrical diols. Application to the synthesis of polysubstituted cyclic ethers

(Matrix Presented) The reaction of symmetrical diols and oligo(ethylene glycol)s with a stoichiometric amount of p-toluenesulfonyl chloride in the presence of silver(I) oxide and a catalytic amount of potassium iodide led selectively to the monotosylate derivatives in high yields. Polysubstituted cyclic ethers were obtained readily upon treatment of the corresponding diols with an excess of silver oxide. The high selectivity was explained on the basis of the difference in acidity between the two hydroxy groups, which undergo an intramolecular hydrogen bonding.

Useful base promoted elaborations of oxiranyl ethers

Functionalized oxiranyl ethers can be regio- and stereoselectively converted into hydroxy oxetanes or cis-diols by treatment with organometallic bases. These two rearrangements can be conveniently carried out either using different reaction conditions sta

A CONVENIENT PREPARATION OF 2-BENZYLOXYACETALDEHYDE

Two new and convenient routes to 2-benzyloxyacetaldehyde (4) that involve oxidative cleavage of (Z)-1,4-dibenzyloxy-2-butene (2) are described.