On the electronic effects of OH groups. Synthesis and investigation of tetrahydroxylated azabicycloheptanes

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Standard

On the electronic effects of OH groups. Synthesis and investigation of tetrahydroxylated azabicycloheptanes. / Gregersen, Anette Valentin; Pedersen, Christian Marcus; Jensen, Henrik Helligsø; Bols, Mikael.

I: Organic & Biomolecular Chemistry, Bind 3, Nr. 8, 2005, s. 1514-1519.

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt

Harvard

Gregersen, AV, Pedersen, CM, Jensen, HH & Bols, M 2005, 'On the electronic effects of OH groups. Synthesis and investigation of tetrahydroxylated azabicycloheptanes', Organic & Biomolecular Chemistry, bind 3, nr. 8, s. 1514-1519. https://doi.org/10.1039/b419154d

APA

Gregersen, A. V., Pedersen, C. M., Jensen, H. H., & Bols, M. (2005). On the electronic effects of OH groups. Synthesis and investigation of tetrahydroxylated azabicycloheptanes. Organic & Biomolecular Chemistry, 3(8), 1514-1519. https://doi.org/10.1039/b419154d

Vancouver

Gregersen AV, Pedersen CM, Jensen HH, Bols M. On the electronic effects of OH groups. Synthesis and investigation of tetrahydroxylated azabicycloheptanes. Organic & Biomolecular Chemistry. 2005;3(8):1514-1519. https://doi.org/10.1039/b419154d

Author

Gregersen, Anette Valentin ; Pedersen, Christian Marcus ; Jensen, Henrik Helligsø ; Bols, Mikael. / On the electronic effects of OH groups. Synthesis and investigation of tetrahydroxylated azabicycloheptanes. I: Organic & Biomolecular Chemistry. 2005 ; Bind 3, Nr. 8. s. 1514-1519.

Bibtex

@article{ae35cf2e42d248bf964aacf8ec627207,
title = "On the electronic effects of OH groups. Synthesis and investigation of tetrahydroxylated azabicycloheptanes",
abstract = "Two stereoisomeric 2,3,5,6-tetrahydroxyazabicyclo[2.2.1]heptanes were synthesised and their base strengths determined. The 2,3,5,6-exo-isomer 1 and the 2,3-exo-5,6-endo-isomer 2 were prepared from the Diels-Alder adduct of Boc-pyrrole and tosylacetylene by a route involving osmium catalyzed dihydroxylation and protection, tosyl group reduction and repeated dihydroxylation. Deprotection gave 1, while 2 was obtained by conversion of the diol into the ditriflate, followed by nucleophilic inversion with KNO(2) and deprotection. Synthesis of the 2,3,5,6-endo-isomer by a similar strategy was attempted but failed. The pK(a) of 1 and 2 was determined to be 7.0 and 6.4 respectively. This means that the change in base strength as a result of stereoisomerism of an OH is smaller in the [2.2.1]-azabicyclic system than in the piperidines. This is explained by a difference in charge-dipole interactions in the two systems.",
keywords = "Amines, Aza Compounds, Cyclization, Electrons, Heptanes, Hydroxides, Molecular Structure",
author = "Gregersen, {Anette Valentin} and Pedersen, {Christian Marcus} and Jensen, {Henrik Helligs{\o}} and Mikael Bols",
year = "2005",
doi = "10.1039/b419154d",
language = "English",
volume = "3",
pages = "1514--1519",
journal = "Organic & Biomolecular Chemistry",
issn = "1470-4358",
publisher = "Royal Society of Chemistry",
number = "8",

}

RIS

TY - JOUR

T1 - On the electronic effects of OH groups. Synthesis and investigation of tetrahydroxylated azabicycloheptanes

AU - Gregersen, Anette Valentin

AU - Pedersen, Christian Marcus

AU - Jensen, Henrik Helligsø

AU - Bols, Mikael

PY - 2005

Y1 - 2005

N2 - Two stereoisomeric 2,3,5,6-tetrahydroxyazabicyclo[2.2.1]heptanes were synthesised and their base strengths determined. The 2,3,5,6-exo-isomer 1 and the 2,3-exo-5,6-endo-isomer 2 were prepared from the Diels-Alder adduct of Boc-pyrrole and tosylacetylene by a route involving osmium catalyzed dihydroxylation and protection, tosyl group reduction and repeated dihydroxylation. Deprotection gave 1, while 2 was obtained by conversion of the diol into the ditriflate, followed by nucleophilic inversion with KNO(2) and deprotection. Synthesis of the 2,3,5,6-endo-isomer by a similar strategy was attempted but failed. The pK(a) of 1 and 2 was determined to be 7.0 and 6.4 respectively. This means that the change in base strength as a result of stereoisomerism of an OH is smaller in the [2.2.1]-azabicyclic system than in the piperidines. This is explained by a difference in charge-dipole interactions in the two systems.

AB - Two stereoisomeric 2,3,5,6-tetrahydroxyazabicyclo[2.2.1]heptanes were synthesised and their base strengths determined. The 2,3,5,6-exo-isomer 1 and the 2,3-exo-5,6-endo-isomer 2 were prepared from the Diels-Alder adduct of Boc-pyrrole and tosylacetylene by a route involving osmium catalyzed dihydroxylation and protection, tosyl group reduction and repeated dihydroxylation. Deprotection gave 1, while 2 was obtained by conversion of the diol into the ditriflate, followed by nucleophilic inversion with KNO(2) and deprotection. Synthesis of the 2,3,5,6-endo-isomer by a similar strategy was attempted but failed. The pK(a) of 1 and 2 was determined to be 7.0 and 6.4 respectively. This means that the change in base strength as a result of stereoisomerism of an OH is smaller in the [2.2.1]-azabicyclic system than in the piperidines. This is explained by a difference in charge-dipole interactions in the two systems.

KW - Amines

KW - Aza Compounds

KW - Cyclization

KW - Electrons

KW - Heptanes

KW - Hydroxides

KW - Molecular Structure

U2 - 10.1039/b419154d

DO - 10.1039/b419154d

M3 - Journal article

C2 - 15827650

VL - 3

SP - 1514

EP - 1519

JO - Organic & Biomolecular Chemistry

JF - Organic & Biomolecular Chemistry

SN - 1470-4358

IS - 8

ER -

ID: 109745252