On the mechanism and origin of the stereoselectivity in iodo-deboronation and chloro-deboronation of hindered alkenyl boronate esters using either ICl-NaOMe or ICl-pyridine

Tetrahedron Letters

Volumn 45, Issue 46, 2004, Pages 8557-8561

  Lightfoot, Andrew P ^a   Twiddle, Steven J R ^b   Whiting, Andrew ^b  

^a GLAXOSMITHKLINE   (United Kingdom)

^b DURHAM UNIVERSITY   (United Kingdom)

Author keywords

Alkenyl boronate; Boronate esters; Chloro deboronation; Iodine monochloride; Iodo deboronation

Indexed keywords

ALKENE DERIVATIVE; BORONIC ACID DERIVATIVE; CHLORIDE; IODINE DERIVATIVE;

ARTICLE; CHEMICAL MODIFICATION; CHEMICAL REACTION; CHLORODEBORONATION; IODODEBORONATION; STEREOCHEMISTRY; TEMPERATURE;

EID: 5644249373     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2004.09.096     Document Type: Article

References (20)

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8. or by hydroboration of phenylacetylene with catecholborane: H.C. Brown, and S.K. Gupta J. Am. Chem. Soc. 94 1972 4370 4371 followed by trans-esterification with hexylene glycol
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11. Private communication with Zanoni, G., University of Pavia, Italy
12. 3) 1.22 (12H, m, 4 × Me), 3.70 (1H, d, J 12 Hz, CHIB), 5.09 (1H, d, J 12 Hz, PhCHCl) and 7.16-7.43 (5H, m, Ph); all other spectroscopic and analytical properties were commensurate with the structure assigned
13. 3) 1.03 (6H, s, 2 × Me), 1.09 (6H, s, 2 × Me), 4.38 (1H, d, J 11 Hz, CHIB), 6.12 (1H, d, J 11 Hz, PhCHCl) and 7.20-7.42 (5H, m, Ph)
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16. 5b starting from 1-nonyne
17. 2 column chromatography or distillation
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20. 2, ICl or IBr were required for complete conversion of catechol esters to the corresponding halides