oxidn. followed by acetylization;

&nbsp;addn. of BCl3 to polymer obtained by hydroboronation of 1,3-pentadiene (cooling), keeping at 20&deg;C for 12 h, at 50&deg;C for 1 h, cooling and addn. of 1,3-pentadiene, heating at 50&deg;C for 15 min;&nbsp;<br /> &nbsp;

<b>With</b>&nbsp; ((C₅-H₁₀)3B₂)x<br /> &nbsp;