# gpqa-diamond / 183

- taskset: [gpqa-diamond](https://harnessreport.com/tasks/gpqa-diamond.md)
- difficulty: difficult
- category: reasoning
- language: 
- runnable from the site: no
- agent timeout: 3600s

## Results by harness

_none yet_

## Instruction

```
What is the correct answer to this question: 
Which sequence of reactions from the following options would lead to the high-yield synthesis of 2-(tert-butyl)-1-ethoxy-3-nitrobenzene, beginning with benzene?

Choices:
  (A) i) tert-butyl chloride/AlCl3 ; ii) HNO3/H2SO4 ; iii) Fe/HCl ; iv) HNO3/H2SO4 ; v) NaNO2/HCl ; vi) H3O+, H2O/Heat ; vii) NaOH/EtBr ; viii) SO3/H2SO4 ; ix) dilute H2SO4
  (B) i) tert-butyl chloride/AlCl3 ; ii) HNO3/H2SO4 iv) ; iii) SO3/H2SO4 ; iv) NaNO2/HCl ; v) dilute H2SO4 ; vi) H3O+, H2O/Heat ; vii) NaOH/EtBr ; viii) Fe/HCl ; ix) HNO3/H2SO4
  (C) i) tert-butyl chloride/AlCl3 ; ii) SO3/H2SO4 ; iii) HNO3/H2SO4 iv) Fe/HCl ; v) NaNO2/HCl ; vi) HNO3/H2SO4 ; vii) H3O+, H2O/Heat ; viii) dilute H2SO4 ix) NaOH/EtBr
  (D) i) HNO3/H2SO4 ; ii) Fe/HCl ; iii) tert-butyl chloride/AlCl3 ; iv) HNO3/H2SO4 ; v) NaNO2/HCl ; vi) SO3/H2SO4 ; vii) dilute H2SO4 ; viii) H3O+, H2O/Heat ; ix) NaOH/EtBr

Let's think step by step:

[First, reason through the problem carefully. Consider all relevant concepts, formulas, and principles. Break down complex problems into manageable steps. Evaluate each answer choice critically.]

Based on your reasoning above, determine the single, most likely answer choice. Then write ONLY the letter of your final answer (A, B, C, or D) to `/app/answer.txt`.

**Important:**
- This is a challenging graduate-level question in biology, physics, or chemistry
- Do not try to solve the question in a single step. Break it down into smaller steps.
- You should ONLY interact with the environment provided to you AND NEVER ASK FOR HUMAN HELP.
- The answer file must contain only a single uppercase letter (A, B, C, or D) with no additional text or explanation
- You can show your work and reasoning before writing the final answer, but the file `/app/answer.txt` should contain only the letter
```
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