Organic Chemistry

(Dana P.) #1
472 CHAPTER 12 Reactions of Alcohols, Ethers, Epoxides, and Sulfur-Containing Compounds

The Heck reactioncouples an aryl, benzyl, or vinyl halide or triflate (Section 12.4)
with an alkene in a basic solution.

The Stille reactioncouples an aryl, benzyl, or vinyl halide or triflate with a stannane.

Aryl and vinyl groups are coupled preferentially, but an alkyl group can be coupled if
a tetraalkylstannane is used.

The Suzuki reactioncouples an aryl, benzyl, or vinyl halide with an organoborane in
a basic solution.

PROBLEM 35

What alkyl halides would you utilize to synthesize the following compounds, using the
organoborane shown?

B

O

O

an organoborane

CH 2

Br

CH 2

CH 2 CH 2 CH 3
+ CH 3 CH 2 CH 2

+ + NaBr

B

O

O

HO B

O

O

+ HO B + NaBr

O

O

Pd(PPh 3 ) 4

CH 3 Br CH 3 CHCH 3
CH 3 CH CH NaOH

Pd(PPh 3 ) 4
NaOH

+ B

O

O

CH

Suzuki reaction

an aryl halide

an aryl triflate

Pd(PPh 3 ) 4

CCH 3

Br

CH 2 CH 2
(CH 3 CH 2 ) 3 N

Pd(PPh 3 ) 4
(CH 3 CH 2 ) 3 N

+ + HBr

+ HOTf

O

CCH 3

CH CH 2

O

CH 3 O

Heck reaction

OTf

+

CH 3 O

a stannane

CH (^3) THF (CH 3 CH 2 CH 2 CH 2 ) 3 SnBr
Stille reaction
CHSn(CH 2 CH 2 CH 2 CH 3 ) 3
Pd(PPh 3 ) 4
Br CH CH 2





    • THF
      Pd(PPh 3 ) 4
      CH 2 CH 2 CH 2 CH 3
      (CH 3 CH 2 CH 2 CH 2 ) 4 Sn
      OTf





    • (CH 3 CH 2 CH 2 CH 2 ) 3 SnOTf
      tetrabutylstannane
      John K. Stillewas a professor of
      chemistry at Colorado State
      University until his untimely death in
      1989 in a commercial air crash on
      his way to a scientific meeting in
      Switzerland.
      BRUI12-437_480r3 27-03-2003 11:51 AM Page 472



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