Organotitanium-induced stereoselective alkylative endo-cleavage of benzyl pentopyranosides
(1998) In Carbohydrate Research 307(1-2). p.13-18- Abstract
The results presented are the first examples where organotitanium reagents induced alkylative endo-cleavage of carbohydrates. The best conditions for the alkylative transfer of a methyl group to benzyl 2-deoxy- 2-C-methyl-4-O-(tert-butyldimethylsilyl)-α-D-arabinopyranoside (1) were the application of one equivalent of AlMe3 followed by four equivalents of MeTiCl3 generated by mixing TiCl4 and ZnMe2 in a ratio 2:1, or, alternatively, treatment of I with two equivalents of 1:1 Me2TiCl2-ZnMe2. Both the yields and diastereoselectivities were comparable with those of the reaction with AlMe3 but the titanium reagents were more reactive and could be applied... (More)
The results presented are the first examples where organotitanium reagents induced alkylative endo-cleavage of carbohydrates. The best conditions for the alkylative transfer of a methyl group to benzyl 2-deoxy- 2-C-methyl-4-O-(tert-butyldimethylsilyl)-α-D-arabinopyranoside (1) were the application of one equivalent of AlMe3 followed by four equivalents of MeTiCl3 generated by mixing TiCl4 and ZnMe2 in a ratio 2:1, or, alternatively, treatment of I with two equivalents of 1:1 Me2TiCl2-ZnMe2. Both the yields and diastereoselectivities were comparable with those of the reaction with AlMe3 but the titanium reagents were more reactive and could be applied at much lower temperatures than the aluminium reagent.
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- author
- Olsson, Roger LU ; Rundström, Pontus ; Persson, Björn LU and Frejd, Torbjörn LU
- organization
- publishing date
- 1998-02
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Alkylation, Endo-cleavage, Organotitanium reagents, Pentopyranosides
- in
- Carbohydrate Research
- volume
- 307
- issue
- 1-2
- pages
- 13 - 18
- publisher
- Elsevier
- external identifiers
-
- scopus:0032004261
- ISSN
- 0008-6215
- DOI
- 10.1016/S0008-6215(97)10079-9
- language
- English
- LU publication?
- yes
- id
- 3f200302-25c5-4b0d-9e14-bf56d863988a
- date added to LUP
- 2019-10-02 10:54:52
- date last changed
- 2023-04-10 02:13:32
@article{3f200302-25c5-4b0d-9e14-bf56d863988a, abstract = {{<p>The results presented are the first examples where organotitanium reagents induced alkylative endo-cleavage of carbohydrates. The best conditions for the alkylative transfer of a methyl group to benzyl 2-deoxy- 2-C-methyl-4-O-(tert-butyldimethylsilyl)-α-D-arabinopyranoside (1) were the application of one equivalent of AlMe<sub>3</sub> followed by four equivalents of MeTiCl<sub>3</sub> generated by mixing TiCl<sub>4</sub> and ZnMe<sub>2</sub> in a ratio 2:1, or, alternatively, treatment of I with two equivalents of 1:1 Me<sub>2</sub>TiCl<sub>2</sub>-ZnMe<sub>2</sub>. Both the yields and diastereoselectivities were comparable with those of the reaction with AlMe<sub>3</sub> but the titanium reagents were more reactive and could be applied at much lower temperatures than the aluminium reagent.</p>}}, author = {{Olsson, Roger and Rundström, Pontus and Persson, Björn and Frejd, Torbjörn}}, issn = {{0008-6215}}, keywords = {{Alkylation; Endo-cleavage; Organotitanium reagents; Pentopyranosides}}, language = {{eng}}, number = {{1-2}}, pages = {{13--18}}, publisher = {{Elsevier}}, series = {{Carbohydrate Research}}, title = {{Organotitanium-induced stereoselective alkylative endo-cleavage of benzyl pentopyranosides}}, url = {{http://dx.doi.org/10.1016/S0008-6215(97)10079-9}}, doi = {{10.1016/S0008-6215(97)10079-9}}, volume = {{307}}, year = {{1998}}, }