Lewis acid catalyzed trans-allylsilylation of unactivated alkynes

Eiji Yoshikawa; Vladimir Gevorgyan; Naoki Asao; Yoshinori Yamamoto

doi:10.1021/ja970443b

Lewis acid catalyzed trans-allylsilylation of unactivated alkynes

Eiji Yoshikawa, Vladimir Gevorgyan, Naoki Asao, Yoshinori Yamamoto

Research output: Contribution to journal › Article › peer-review

47 Citations (Scopus)

Abstract

The addition of different substituted allylsilanes 2 to unactivated alkynes 1 in the presence of catalytic mounts of HfCl₄ or the EtAlCl₂- TMSC1 catalyst system produced in high yields the silylated 1,4-dienes 3 regio- and stereoselectively. The exclusive trans manner of addition was confirmed by analysis of crude reaction mixtures by ¹H NMR and capillary GLC methods. Good agreement of relative reactivities of reaction of various allylsilanes 2a-e toward phenylacetylene (1a) in the presence of HfCl₄ with the relative reaction rates of 2a-e with carbenium ions supported the involvement of cationic species 11 as a reaction intermediate. The mechanisms for the HfCl₄ and EtAlCl₂-TMS catalyzed trans-allylsilylation of alkynes are proposed.

Original language	English
Pages (from-to)	6781-6786
Number of pages	6
Journal	Journal of the American Chemical Society
Volume	119
Issue number	29
DOIs	https://doi.org/10.1021/ja970443b
Publication status	Published - 1997 Jul 23

ASJC Scopus subject areas

Catalysis
Chemistry(all)
Biochemistry
Colloid and Surface Chemistry

Access to Document

10.1021/ja970443b

Cite this

@article{6eec173f8d984840b36d14c9558c401e,

title = "Lewis acid catalyzed trans-allylsilylation of unactivated alkynes",

abstract = "The addition of different substituted allylsilanes 2 to unactivated alkynes 1 in the presence of catalytic mounts of HfCl4 or the EtAlCl2- TMSC1 catalyst system produced in high yields the silylated 1,4-dienes 3 regio- and stereoselectively. The exclusive trans manner of addition was confirmed by analysis of crude reaction mixtures by 1H NMR and capillary GLC methods. Good agreement of relative reactivities of reaction of various allylsilanes 2a-e toward phenylacetylene (1a) in the presence of HfCl4 with the relative reaction rates of 2a-e with carbenium ions supported the involvement of cationic species 11 as a reaction intermediate. The mechanisms for the HfCl4 and EtAlCl2-TMS catalyzed trans-allylsilylation of alkynes are proposed.",

author = "Eiji Yoshikawa and Vladimir Gevorgyan and Naoki Asao and Yoshinori Yamamoto",

year = "1997",

month = jul,

day = "23",

doi = "10.1021/ja970443b",

language = "English",

volume = "119",

pages = "6781--6786",

journal = "Journal of the American Chemical Society",

issn = "0002-7863",

publisher = "American Chemical Society",

number = "29",

}

TY - JOUR

T1 - Lewis acid catalyzed trans-allylsilylation of unactivated alkynes

AU - Yoshikawa, Eiji

AU - Gevorgyan, Vladimir

AU - Asao, Naoki

AU - Yamamoto, Yoshinori

PY - 1997/7/23

Y1 - 1997/7/23

N2 - The addition of different substituted allylsilanes 2 to unactivated alkynes 1 in the presence of catalytic mounts of HfCl4 or the EtAlCl2- TMSC1 catalyst system produced in high yields the silylated 1,4-dienes 3 regio- and stereoselectively. The exclusive trans manner of addition was confirmed by analysis of crude reaction mixtures by 1H NMR and capillary GLC methods. Good agreement of relative reactivities of reaction of various allylsilanes 2a-e toward phenylacetylene (1a) in the presence of HfCl4 with the relative reaction rates of 2a-e with carbenium ions supported the involvement of cationic species 11 as a reaction intermediate. The mechanisms for the HfCl4 and EtAlCl2-TMS catalyzed trans-allylsilylation of alkynes are proposed.

AB - The addition of different substituted allylsilanes 2 to unactivated alkynes 1 in the presence of catalytic mounts of HfCl4 or the EtAlCl2- TMSC1 catalyst system produced in high yields the silylated 1,4-dienes 3 regio- and stereoselectively. The exclusive trans manner of addition was confirmed by analysis of crude reaction mixtures by 1H NMR and capillary GLC methods. Good agreement of relative reactivities of reaction of various allylsilanes 2a-e toward phenylacetylene (1a) in the presence of HfCl4 with the relative reaction rates of 2a-e with carbenium ions supported the involvement of cationic species 11 as a reaction intermediate. The mechanisms for the HfCl4 and EtAlCl2-TMS catalyzed trans-allylsilylation of alkynes are proposed.

UR - http://www.scopus.com/inward/record.url?scp=0030859171&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030859171&partnerID=8YFLogxK

U2 - 10.1021/ja970443b

DO - 10.1021/ja970443b

M3 - Article

AN - SCOPUS:0030859171

SN - 0002-7863

VL - 119

SP - 6781

EP - 6786

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

IS - 29

ER -

Lewis acid catalyzed trans-allylsilylation of unactivated alkynes

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this