Synthesis of cyclopropanes via organoiron methodology: stereoselective preparation of cis-2-(2’-carboxycyclopropyl)glycine

A stereoselective route to cis-2-(2′-carboxycyclopropyl)glycine has been developed. exo-Nucleophilic addition to the (bicyclo[5.1.0]octadienyl)iron(1+) cation establishes the relative stereochemistry at the cyclopropane ring and the α-stereocenter. Subsequent removal of the metal and cleavage of the cyclic diene gave the protected target 10, which upon hydrolysis gave 1. A stereoselective route to cis-2-(2′-carboxycyclopropyl)glycine has been developed. exo-Nucleophilic addition to the (bicyclo[5.1.0]octadienyl)iron(1+) cation establishes the relative stereochemistry at the cyclopropane ring and the α-stereocenter

Reactivity of (Bicyclo[5.1.0]octadienyl)iron(1+) Cations: Application to the Synthesis of cis-2-(2’-carboxycyclopropyl)glycines

The addition of carbon and heteroatom nucleophiles to (bicyclo[5.1.0]octadienyl)Fe(CO)2L+ cations 5 or 8 (L = CO, PPh3) generally proceeds via attack at the dienyl terminus on the face of the ligand opposite to iron to generate 6-substituted (bicyclo[5.1.0]octa-2,4-diene)iron complexes (11 or 13). In certain cases, these products are unstable with respect to elimination of a proton and the nucleophilic substituent to afford (cyclooctatetraene)Fe(CO)2L (4 or 7). Decomplexation of 13f, arising from addition of phthalimide to 8, gave N-(bicyclo[5.1.0]octa-3,5-dien-2-yl)phthalimide (19). Oxidative cleavage of 19 (RuCl3/NaIO4) followed by esterification gave the cyclopropane diester 22, which upon hydrolysis gave cis-2-(2‘-carboxycyclopropyl)glycine (CCG-III, 18) (eight steps from 4, 43% overall yield). This methodology was also utilized for preparation of stereospecifically deuterated CCG-III (d-18) and optically enriched (−)-18. Deprotonation of 22 resulted in cyclopropane ring opening to afford the benzoindolizidine (23)

Crystal structure of \u3cem\u3ecis\u3c/em\u3e-2-(2-carboxycyclopropyl)-glycine (CCG-III) monohydrate

The title compound, C6H9NO4·H2O [systematic name: (αR,1R,2S)-rel-α-amino-2-carb­oxy­cyclo­propane­acetic acid monohydrate], crystallizes with two organic mol­ecules and two water mol­ecules in the asymmetric unit. The space group is P21 and the organic mol­ecules are enanti­omers, thus this is an example of a `false conglomerate\u27 with two mol­ecules of opposite handedness in the asymmetric unit (r.m.s. overlay fit = 0.056 Å for one mol­ecule and its inverted partner). Each mol­ecule exists as a zwitterion, with proton transfer from the amino acid carb­oxy­lic acid group to the amine group. In the crystal, the components are linked by N-H···O and O-H···O hydrogen bonds, generating (100) sheets. Conformationally restricted glutamate analogs are of inter­est due to their selective activation of different glutamate receptors, and the naturally occurring (+)-CCG-III is an inhibitor of glutamate uptake and the key geometrical parameters are discussed

Clara Wallock Interview Transcript

Clara Wallock discusses her life and growing up in Mt. Vernonhttps://digital.kenyon.edu/jews_interviews/1003/thumbnail.jp

Deconstructing and Reconstructing Guidebook Ideologies: The Influence of Travel Guidebooks and the Media on Nature Tourism Projects in Costa Rica and Tanzania

Senior Project submitted to The Division of Multidisciplinary Studies of Bard College

Spectral Data for Synthesis of Cyclopropanes via Organoiron Methodology: Stereoselective Preparation of Bi(cyclopropyl)s

Spectral data created in the course of the research project. Supports specific findings in Synthesis of Cyclopropanes via Organoiron Methodology: Stereoselective Preparation of Bi(cyclopropyl)s . Cyclopropanation of [2-(alkenyl)pentenediyl]Fe(CO)3 complexes (4) proceeds in a diastereoselective fashion to afford [2-(cyclopropyl)pentenediyl]Fe(CO)3. The relative stereochemistry of the products was established by X-ray crystallography. The diastereoselectivity is rationalized on approach of the cyclopropanation reagent on the sterically more exposed face of 4. Oxidatively induced reductive elimination afforded stereodefined bi(cyclopropyl)s

Sprectral data for Generation of Molecular Complexity from Cyclooctatetraene Using Dienyliron and Olefin Metathesis

Spectral data used in the course of researching Generation of molecular complexity from cyclooctatetraene using dienyliron and olefin metathesis methodology . Transformation of the simple hydrocarbon cyclooctatetraene into a variety of polycyclic skeletons was achieved by sequential coordination to iron, reaction with electrophiles followed by allylated nucleophiles, decomplexation and olefin metathesis

Synthesis of Cyclopropanes via Organoiron Methodology: Preparation and Rearrangement of Divinylcyclopropanes

Addition of alkenyl Grignard reagents to (1-methoxycarbonylpentadienyl)iron(1+) cation generates the corresponding (2-alkenylpent-3-en-1,5-diyl)iron complexes. Oxidatively induced-reductive elimination of these complexes gives divinylcyclopropanes which can undergo subsequent Cope rearrangement to give 1,4-cycloheptadienes

Interview with Mrs. Helen Zelkowitz and Mrs. Clara Wallock

Helen Zelkowitz and [Clara Wallock] discuss their lives growing up in Mount Vernon and their families.https://digital.kenyon.edu/jews_interviews/1001/thumbnail.jp

Embedding Mindfulness Practice in Entry-Level Occupational Therapy Education Program: Experiences and Outcomes

Objective: To embed mindfulness practice into an entry-level occupational therapy curriculum and assess outcomes to reduce student stress and promote well-being