Stereocomplementary Syntheses of 1,ω-Distannylated E,Z-Isomeric Conjugated Trienes, Tetraenes, and Pentaenes

✍ Scribed by Dr. Jochen Burghart; Dr. Achim Sorg; Prof. Dr. Reinhard Brückner

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 515 KB
• Volume: 17
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.201001629

✦ Synopsis

Abstract

Stereoselective syntheses of 1,6‐bis(tributylstannyl)hexa‐1,3,5‐trienes, 1,8‐bis(tributylstannyl)octa‐1,3,5,7‐tetraenes, and 1,10‐bis(tributylstannyl)deca‐1,3,5,7,9‐pentaenes with various methylation patterns were achieved based on stereocomplementary CC bond‐forming reactions. All‐E isomers resulted from Ramberg–Bäcklund rearrangements of distannylated diallyl‐, allylpentadienyl‐, or bis‐ (pentadienyl)sulfones. Mono‐Z‐configured 1,ω‐bis(tributylstannyl)‐1,3,5‐polyenes emerged from (Sylvestre–)Julia olefinations of Bu~3~Sn‐substituted enals or dienals with Bu~3~Sn‐substituted allyl or pentadienyl benzothiazolylsulfones. Related Ramberg–Bäcklund approaches provided all‐E‐1‐bromo‐6‐(tributylstannyl)hexa‐1,3,5‐triene but not all‐E‐1‐(tetramethyldioxaborolanyl)‐6‐(tributylstannyl)hexa‐1,3,5‐triene.