Biomedical subjects

Joel D Moore

Publications and source records attributed to Joel D Moore.

7 recordsLinked to original sources

PubMed2005

Multivalent activation in temporary phosphate tethers: a new tether for small molecule synthesis.

[reaction: see text]. A new tether for small molecule synthesis is reported. This functionally active tether mediates the desymmetrization of a pseudo-C(2)-symmetric tris-allylic phosphate triester to generate a P-chiral bicyclo[4.3.1]phosphate containing ample steric and stereoelectronic differentiation for investigating chemo-, regio-, and stereoselective transformations. Overall, the method reported herein demonstrates a fundamentally new role of phosphates in synthesis and provides differentiated polyol building blocks for use in natural product synthesis.

Biological Products↗

PubMed2004

Development of high-load, soluble oligomeric sulfonate esters via ROM polymerization: application to the benzylation of amines.

The development of high-load, soluble oligomeric sulfonate esters, generated via ROM polymerization, and their utility in the facile benzylation of an array of amines is reported. These polymeric sulfonate esters exist as free-flowing powders, are stable at refrigerated temperatures, and are readily dissolved in CH(2)Cl(2). Following the benzylation event, purification is attained via simple filtration, followed by solvent removal to deliver the desired benzylated product in good to excellent yield and high purity. [structure: see text]

Alkylating Agents↗

PubMed2003

High-load, ROMP-generated oligomeric bis-acid chlorides: design of soluble and insoluble nucleophile scavengers.

[reaction: see text] An efficient strategy for scavenging a host of nucleophiles utilizing an oligomeric bis-acid chloride (OBAC), generated from the ROM polymerization of trans-bicyclo[2.2.1]hept-5-ene-2,3-dicarbonyl dichloride, is described. The reactivity and high load of the OBAC reagent is exploited in the scavenging of amines, alcohols, and thiols that are present in excess following a common benzoylation event. Following the scavenging event, these oligomers can be precipitated with EtOAc and filtered (SiO(2)), leaving benzoylated nucleophiles in excellent yield and purity.

Acids↗

PubMed2003

ROMP-generated oligomeric sulfonyl chlorides as versatile soluble scavenging agents.

[reaction: see text] A new method for homogeneous nucleophilic scavenging employing oligomeric sulfonyl chloride (OSC) reagents is described. The method utilizes OSC to rapidly scavenge a variety of amines that are present in excess. The OSC reagents are generated from ROM polymerization of 2-chlorosulfonyl-5-norbornene utilizing the second generation Grubbs catalyst to produce oligomers of varying size as stable, free-flowing powders. Following the scavenging event, these oligomers are precipitated with ethyl acetate leaving products in excellent yield and purity.

Amines↗

PubMed2002

Conformationally constrained alpha-boc-aminophosphonates via transition metal-catalyzed/curtius rearrangement strategies.

A transition metal-catalyzed/Curtius rearrangement sequence toward the development of conformationally constrained alpha-Boc-aminophosphonates 2-6 is described. An approach using the versatile tert-butylphosphonoacetate moieties 1a and 1b to derive an array of mono- and bicyclic alpha-Boc-aminophosphonate systems is presented. Conformational constraint is incorporated using either the ring-closing metathesis reaction catalyzed by the first generation Grubbs catalyst or intramolecular cyclopropanation mediated by Rh2(OAc)4. Using the tert-butyl ester functionality in 1a or 1b as a potential amino group, the Curtius rearrangement provides an efficient route toward the target alpha-Boc-aminophosphonates.

Amines↗

PubMed2002

Double diastereoselective intramolecular cyclopropanation to P-chiral [3.1.0]-bicyclic phosphonates.

[reaction: see text] A double diastereotopic differentiation strategy on a phosphonoacetate template is described. The approach utilizes Rh(2)(OAc)(4)-catalyzed intramolecular cyclopropanation (ICP) employing the (R)-pantolactone auxiliary in the ester functionality of the phosphonoacetate. The olefinic diastereofacial selectivity is governed by inherent electronic and steric interactions in the reacting carbene intermediate, while the group selectivity is dictated by the chiral auxiliary. This approach is being developed as an effective method to access bicyclic P-chiral phosphonates.

Catalysis↗

PubMed2002

Scavenge-ROMP-filter: a facile strategy for soluble scavenging via norbornenyl tagging of electrophilic Reagents.

[reaction: see text] A new "chemical tagging" method for homogeneous electrophilic scavenging is described. The method utilizes 5-norbornene-2-methanol to scavenge/tag a variety of electrophiles that are present in excess. Once tagging is complete, the crude reaction mixture is subjected to a rapid ROM polymerization event utilizing the second generation Grubbs catalyst. This process yields a polymer that can be precipitated with methanol or ether/hexane, leaving products in excellent yield and purity.

Alcohols↗