Let's determine the absolute configuration (R or S) for **both chiral centers** (carbon 1 and carbon 2) in the given molecule. --- ## **Step 1: Assign Priorities (Cahn-Ingold-Prelog Rules)** ### **For Carbon 1:** Substituents: - Ph (Phenyl) - H - Cl - C2 (the other chiral carbon) Assign priorities based on atomic number: 1. **Cl** (atomic number 17) – highest priority 2. **Ph** (phenyl group, C attached to aromatic ring) 3. **C2** (attached to OH, H, and C1) 4. **H** (atomic number 1) – lowest priority ### **For Carbon 2:** Substituents: - OH - H - C1 (attached to Cl, Ph, H) - (implied) another group, but from the structure, it's a part of the ring Assign priorities: 1. **OH** (Oxygen, atomic number 8) – highest priority 2. **C1** (attached to Cl, Ph, H) 3. **rest of the ring** (likely a C attached to H, C, C) 4. **H** (atomic number 1) – lowest priority --- ## **Step 2: Assign R/S Configuration** ### **For Carbon 1:** 1. Orient the molecule so that the lowest priority group (H) is going away from you. 2. Trace the path from priority 1 (Cl) → 2 (Ph) → 3 (C2). #### **Order: Cl → Ph → C2** - If this path is **clockwise**, it's **R**. - If this path is **counterclockwise**, it's **S**. #### **From the structure:** - Cl is down, Ph is up, H is to the right, C2 is to the left. If H is going away, the order Cl → Ph → C2 is **clockwise**. **So, Carbon 1 is (R).** --- ### **For Carbon 2:** 1. Orient so that H is away from you. 2. Trace the path from priority 1 (OH) → 2 (C1) → 3 (rest of ring). #### **Order: OH → C1 → rest of ring** - If this path is **clockwise**, it's **R**. - If **counterclockwise**, it's **S**. #### **From the structure:** - OH is left, C1 is up, H is into the plane, rest of ring is right. With H away, OH → C1 → rest of ring traces a **counterclockwise** path. **So, Carbon 2 is (S).** --- ## **Final Answer** ### **Absolute Configurations:** - **Carbon 1:** (R) - **Carbon 2:** (S) --- ### **Summary Table** | Chiral Center | Configuration | |---------------|:------------:| | 1 | R | | 2 | S | --- **If you need visual step-by-step diagrams, let me know!**