Chapter 19, Problem 19.61P

Interpretation Introduction

(a)

Interpretation:

The Major organic product of the given reaction is to be determined.

Concept introduction:

The palladium catalyzed reactions are namely Suzuki coupling and Heck coupling which formed new $\text{C-C}$ bond. In Suzuki coupling reaction, a vinylic or aryl halide $\text{R-X}$ is treated with an organometallic compound $\text{R’-B}{\left(\text{OR”}\right)}_{\text{2}}$ and a palladium catalyst $\left(\text{PdLn}\right)$ under basic condition. Suzuki reaction is stereospecific involving possible $\text{E/Z}$ isomerism usually with retention of configuration. Similar to the Suzuki reaction, the Heck reaction can couple one vinylic or aryl group to another. If $\text{R-X}$ halide in a Heck reaction is vinylic, the configuration about the double bond is retained. If $\text{H-R’}$ is vinylic and has an attached substituent at the opposite end of the $\text{C=C}$, then $\text{R}$ and the substituent will be trans to each other in the product.

Answer to Problem 19.61P

The major product of given Suzuki reaction of $\text{R-X}$ and $\text{R’-B}{\left(\text{OR”}\right)}_{\text{2}}$ is

Explanation of Solution

The Suzuki coupling reaction forms a new $\text{C-C}$ bond between $\text{R-X}$ and $\text{R’-B}{\left(\text{OR”}\right)}_{\text{2}}$ in presence of palladium catalyst. The new $\text{C-C}$ bond is formed between $\text{R}$ group of aryl halide and $\text{R’}$ group of boron containing compound. The reaction proceeds with retention of configuration.

Therefore, the overall Suzuki reaction is

Conclusion

Suzuki reaction, involving possible $\text{E/Z}$ isomerism, usually proceeds with retention of configuration $\text{C=C}$ double bond.

Interpretation Introduction

(b)

Interpretation:

The Major organic product of the given reaction is to be determined.

Concept introduction:

The palladium catalyzed reactions are namely Suzuki coupling and Heck coupling which formed new $\text{C-C}$ bond. In Suzuki coupling reaction, a vinylic or aryl halide $\text{R-X}$ is treated with an organometallic compound $\text{R’-B}{\left(\text{OR”}\right)}_{\text{2}}$ and a palladium catalyst $\left(\text{PdLn}\right)$ under basic condition. Suzuki reaction is stereospecific involving possible $\text{E/Z}$ isomerism usually with retention of configuration. Similar to the Suzuki reaction, the Heck reaction can couple one vinylic or aryl group to another. If $\text{R-X}$ halide in a Heck reaction is vinylic, the configuration about the double bond is retained. If $\text{H-R’}$ is vinylic and has an attached substituent at the opposite end of the $\text{C=C}$, then $\text{R}$ and the substituent will be trans to each other in the product.

Answer to Problem 19.61P

The major product of the given Suzuki reaction of $\text{R-X}$ and $\text{R’-B}{\left(\text{OR”}\right)}_{\text{2}}$ is

Explanation of Solution

The Suzuki coupling reaction forms a new $\text{C-C}$ bond between $\text{R-X}$ and $\text{R’-B}{\left(\text{OR”}\right)}_{\text{2}}$ in presence of palladium catalyst. The new $\text{C-C}$ bond is formed between $\text{R}$ group of aryl halide and $\text{R’}$ group of boron containing compound. The reaction proceeds with retention of configuration.

Therefore, the overall Suzuki reaction is

Conclusion

Suzuki reaction involving possible E/Z isomerism usually proceeds with retention of configuration of C=C double bond.

Interpretation Introduction

(c)

Interpretation:

The Major organic product of the given reaction is to be determined.

Concept introduction:

The palladium catalyzed reactions are namely Suzuki coupling and Heck coupling which formed new $\text{C-C}$ bond. In Suzuki coupling reaction, a vinylic or aryl halide $\text{R-X}$ is treated with an organometallic compound $\text{R’-B}{\left(\text{OR”}\right)}_{\text{2}}$ and a palladium catalyst $\left(\text{PdLn}\right)$ under basic condition. Suzuki reaction is stereospecific involving possible $\text{E/Z}$ isomerism usually with retention of configuration. Similar to the Suzuki reaction, the Heck reaction can couple one vinylic or aryl group to another. If $\text{R-X}$ halide in a Heck reaction is vinylic, the configuration about the double bond is retained. If $\text{H-R’}$ is vinylic and has an attached substituent at the opposite end of the $\text{C=C}$, then $\text{R}$ and the substituent will be trans to each other in the product.

Answer to Problem 19.61P

The major product of given Heck reaction of $\text{R-X}$ and $\text{R’-H}$ is

Explanation of Solution

In the given Heck reaction, a new $\text{C-C}$ bond is formed between $\text{R}$ from $\text{R-X}$ and $\text{R’}$ from $\text{H-R’}$. If $\text{H-R’}$ is vinylic and has an attached substituent that is $\text{Ph}$ at the opposite end of the $\text{C=C}$, then $\text{R}$ and the substituent attached are trans to each other.

Therefore, the overall Heck reaction is

Conclusion

If the $\text{R-X}$ halide in Heck reaction is vinylic, the configuration about the double bond is retained. If $\text{H-R’}$ is vinylic and has an attached substituent at the opposite end of $\text{C=C}$, then $\text{R}$ and the substituent will be trans to each other in the product.

Interpretation Introduction

(d)

Interpretation:

The Major organic product of the given reaction is to be determined.

Concept introduction:

The palladium catalyzed reactions are namely Suzuki coupling and Heck coupling which formed new $\text{C-C}$ bond. In Suzuki coupling reaction, a vinylic or aryl halide $\text{R-X}$ is treated with an organometallic compound $\text{R’-B}{\left(\text{OR”}\right)}_{\text{2}}$ and a palladium catalyst $\left(\text{PdLn}\right)$ under basic condition. Suzuki reaction is stereospecific involving possible $\text{E/Z}$ isomerism usually with retention of configuration. Similar to the Suzuki reaction, the Heck reaction can couple one vinylic or aryl group to another. If $\text{R-X}$ halide in a Heck reaction is vinylic, the configuration about the double bond is retained. If $\text{H-R’}$ is vinylic and has an attached substituent at the opposite end of the $\text{C=C}$, then $\text{R}$ and the substituent will be trans to each other in the product.

Answer to Problem 19.61P

The major product of given Heck reaction of $\text{R-X}$ and $\text{R’-H}$ is

Explanation of Solution

The ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}\text{CH=CH}$ substituent on $\text{R’-H}$ becomes trans to the $\text{R}$ substituent from $\text{R-X}$. In this reaction, the Cis configuration about the $\text{C=C}$ in the $\text{R-Br}$ reactant is retained.

Therefore, the overall Heck reaction is

Conclusion

If the $\text{R-X}$ halide in Heck reaction is vinylic, the configuration about the double bond is retained. If $\text{R’-H}$ is vinylic and has an attached substituent at the opposite end of $\text{C=C}$, then $\text{R}$ and the substituent will be trans to each other in the product.