The University of Southampton
University of Southampton Institutional Repository

Competitive formation of cis and trans derivatives in the nucleophilic substitution reactions of cyclophosphazenes having a mono-spiro P–NHR group

Competitive formation of cis and trans derivatives in the nucleophilic substitution reactions of cyclophosphazenes having a mono-spiro P–NHR group
Competitive formation of cis and trans derivatives in the nucleophilic substitution reactions of cyclophosphazenes having a mono-spiro P–NHR group
Nucleophilic substitution reactions of N(3)P(3)Cl(4)[NH(CH(2))(3)NMe] (1) and N(3)P(3)Cl(4)[NH(CH(2))(3)O] (2) with mono-functional alcohols (methanol, 2,2,2-trifluoroethanol, phenol) and a secondary amine (pyrrolidine) were used to investigate the relationship between the incoming nucleophile and the proportions of products with substituents that are cis or trans to the spiro NH moiety. The reaction products were characterized by elemental analysis, mass spectrometry, (1)H and (31)P NMR spectroscopy and the configurational isomers by X-ray crystallography. Six products have been characterised with the substituent cis to the spiro NH group for the alcohol (methanol, phenol) and pyrrolidine derivatives of both compounds 1 and 2, compared to just one derivative with the substituent trans to the spiro NH group, that for the pyrrolidine derivative of compound 2. For each reaction the relative proportions of cis and trans isomers were determined by (31)P NMR measurements of the reaction mixtures. It was found that the reactions of compound 1 with all three alcohols and of compound 2 with methanol lead to exclusive formation of isomers with the substituent cis to the NH moiety, whereas all other reactions lead to mixtures of cis and trans isomers in different ratios under standard reaction conditions. However, when crown ether is included in the reaction medium for the reactions of compound 2 with both 2,2,2-trifluoroethanol and phenol, it is found that only cis isomers are formed. All these results are rationalised in terms of the competition between at least two effects; the cis-directing effect by hydrogen bonding of the incoming nucleophile to the spiro N-H group already present on the cyclophophazene ring and the cis-directing effect of the sodium cation coordinating to the oxygen lone pairs of the P-O moiety of the spiro ring
0300-9246
4959-4969
Beşli, Serap
63ec1cf4-d0d6-4982-9e0a-c632f1f98d08
Coles, Simon J.
3116f58b-c30c-48cf-bdd5-397d1c1fecf8
Davies, David B.
675b90e6-0c3c-468b-9996-326220517cc6
Kılıç, Adem
565a42ec-2d18-4142-8b37-bb74b244b2f5
Okutan, Elif
962b5f3a-09d5-417f-89df-39ba9a3be3f5
Shaw, Robert A.
a9ecde60-6fe9-4b5d-86e3-77cd5dcfaab8
Eçik, Esra Tanrıverdi
fbebdebb-d388-40b6-8139-12b0555b8c0e
Çiftçi, Gönül Yenilmez
ec263230-06cb-46be-b546-f366b4a38438
Beşli, Serap
63ec1cf4-d0d6-4982-9e0a-c632f1f98d08
Coles, Simon J.
3116f58b-c30c-48cf-bdd5-397d1c1fecf8
Davies, David B.
675b90e6-0c3c-468b-9996-326220517cc6
Kılıç, Adem
565a42ec-2d18-4142-8b37-bb74b244b2f5
Okutan, Elif
962b5f3a-09d5-417f-89df-39ba9a3be3f5
Shaw, Robert A.
a9ecde60-6fe9-4b5d-86e3-77cd5dcfaab8
Eçik, Esra Tanrıverdi
fbebdebb-d388-40b6-8139-12b0555b8c0e
Çiftçi, Gönül Yenilmez
ec263230-06cb-46be-b546-f366b4a38438

Beşli, Serap, Coles, Simon J., Davies, David B., Kılıç, Adem, Okutan, Elif, Shaw, Robert A., Eçik, Esra Tanrıverdi and Çiftçi, Gönül Yenilmez (2011) Competitive formation of cis and trans derivatives in the nucleophilic substitution reactions of cyclophosphazenes having a mono-spiro P–NHR group. Dalton Transactions, 40 (18), 4959-4969. (doi:10.1039/c1dt10176e).

Record type: Article

Abstract

Nucleophilic substitution reactions of N(3)P(3)Cl(4)[NH(CH(2))(3)NMe] (1) and N(3)P(3)Cl(4)[NH(CH(2))(3)O] (2) with mono-functional alcohols (methanol, 2,2,2-trifluoroethanol, phenol) and a secondary amine (pyrrolidine) were used to investigate the relationship between the incoming nucleophile and the proportions of products with substituents that are cis or trans to the spiro NH moiety. The reaction products were characterized by elemental analysis, mass spectrometry, (1)H and (31)P NMR spectroscopy and the configurational isomers by X-ray crystallography. Six products have been characterised with the substituent cis to the spiro NH group for the alcohol (methanol, phenol) and pyrrolidine derivatives of both compounds 1 and 2, compared to just one derivative with the substituent trans to the spiro NH group, that for the pyrrolidine derivative of compound 2. For each reaction the relative proportions of cis and trans isomers were determined by (31)P NMR measurements of the reaction mixtures. It was found that the reactions of compound 1 with all three alcohols and of compound 2 with methanol lead to exclusive formation of isomers with the substituent cis to the NH moiety, whereas all other reactions lead to mixtures of cis and trans isomers in different ratios under standard reaction conditions. However, when crown ether is included in the reaction medium for the reactions of compound 2 with both 2,2,2-trifluoroethanol and phenol, it is found that only cis isomers are formed. All these results are rationalised in terms of the competition between at least two effects; the cis-directing effect by hydrogen bonding of the incoming nucleophile to the spiro N-H group already present on the cyclophophazene ring and the cis-directing effect of the sodium cation coordinating to the oxygen lone pairs of the P-O moiety of the spiro ring

Full text not available from this repository.

More information

e-pub ahead of print date: 29 March 2011
Organisations: Organic Chemistry: Synthesis, Catalysis and Flow

Identifiers

Local EPrints ID: 346125
URI: https://eprints.soton.ac.uk/id/eprint/346125
ISSN: 0300-9246
PURE UUID: c6cba9b0-53ec-4732-b821-2fa49cd88196
ORCID for Simon J. Coles: ORCID iD orcid.org/0000-0001-8414-9272

Catalogue record

Date deposited: 19 Dec 2012 12:26
Last modified: 06 Jun 2018 12:54

Export record

Altmetrics

Contributors

Author: Serap Beşli
Author: Simon J. Coles ORCID iD
Author: David B. Davies
Author: Adem Kılıç
Author: Elif Okutan
Author: Robert A. Shaw
Author: Esra Tanrıverdi Eçik
Author: Gönül Yenilmez Çiftçi

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×