<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@H]3[C@H](O3)C4=CC=C(OC)C=C41, Substrate A](/media/uploads/586cc288-8894-4d9f-9e26-a50a6b6d7c71.png)</MultiModal>

This substrate $\mathbf{A}$ can undergo hydrolysis under acidic conditions, generating a compound containing three six-membered rings. Please consider the stereochemistry of the cyclic transition state and select the structure of the major product.
<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@H]3[C@H](O3)C4=CC=C(OC)C=C41,底物A](/media/uploads/586cc288-8894-4d9f-9e26-a50a6b6d7c71.png)</MultiModal>

该底物$\mathbf{A}$可以在酸性条件下发生水解，生成某含有三个六元环的化合物。请考虑环状过渡态的立体化学，选出主要产物的结构。
All other options are incorrect
<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/dc00a6a0-f8ad-4c2c-849a-a93ab5ccd96a.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@H](O)[C@@H](O)C3=CC=C(OC)C=C31](/media/uploads/4898d824-3926-4813-96b0-3ae54c3fff58.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/833ad9d2-5e0b-4416-a03c-823c1f542358.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@H](O)[C@@H](O)C3=CC=C(OC)C=C31](/media/uploads/24cc67c2-02fb-437b-a29e-3331997aaacc.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@@](CCCC2)([H])[C@@H](O)[C@@H](O)C3=CC=C(OC)C=C31](/media/uploads/ae265b0f-d5bb-4cc2-a36b-ad504cc238ca.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@@](CCCC2)([H])[C@H](O)[C@@H](O)C3=CC=C(OC)C=C31](/media/uploads/53c133c5-9f2d-4f63-9353-6db661c8446a.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@@](CCCC2)([H])[C@@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/41ae522e-b742-48c9-9f0d-781a99a76bc8.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@@](CCCC2)([H])[C@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/ef0a1325-167d-4faf-be95-4d9cf6c7e301.png)</MultiModal>
其他选项均不正确
<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/dc00a6a0-f8ad-4c2c-849a-a93ab5ccd96a.png)</MultiModal>

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@H](O)[C@@H](O)C3=CC=C(OC)C=C31](/media/uploads/4898d824-3926-4813-96b0-3ae54c3fff58.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/833ad9d2-5e0b-4416-a03c-823c1f542358.png)</MultiModal>

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@H](O)[C@@H](O)C3=CC=C(OC)C=C31](/media/uploads/24cc67c2-02fb-437b-a29e-3331997aaacc.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@@](CCCC2)([H])[C@@H](O)[C@@H](O)C3=CC=C(OC)C=C31](/media/uploads/ae265b0f-d5bb-4cc2-a36b-ad504cc238ca.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@@](CCCC2)([H])[C@H](O)[C@@H](O)C3=CC=C(OC)C=C31](/media/uploads/53c133c5-9f2d-4f63-9353-6db661c8446a.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@@](CCCC2)([H])[C@@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/41ae522e-b742-48c9-9f0d-781a99a76bc8.png)</MultiModal>
<MultiModal>![[H][C@@]12[C@@](CCCC2)([H])[C@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/ef0a1325-167d-4faf-be95-4d9cf6c7e301.png)</MultiModal>
Methoxy has a certain conjugation electron-donating effect, which can stabilize benzylic carbocations.

<Checkpoint>[Methoxy has a certain conjugation electron-donating effect, which can stabilize benzylic carbocations.](1)</Checkpoint>

Therefore, the three-membered ring first undergoes ring-opening under acidic conditions to form carbocation intermediate 1.

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@](O)([H])[C+]([H])C3=CC=C(OC)C=C31](/media/uploads/ba83be3a-3353-4889-a87c-a982148c2394.png)</MultiModal>

<Checkpoint>[[H][C@@]12[C@](CCCC2)([H])[C@@](O)([H])[C+]([H])C3=CC=C(OC)C=C31](1)</Checkpoint>

The conformation of the intermediate is

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@](O)([H])[C+]([H])C3=CC=C(OC)C=C31](/media/uploads/49c4a440-8f00-4779-97a9-6ed4a5368bee.png)</MultiModal>

The Newman projection formula when $\mathrm{H_2O}$ undergoes nucleophilic attack can be drawn

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@](O)([H])[C+]([H])C3=CC=C(OC)C=C31](/media/uploads/b5d8d3ad-796e-42a7-8f3e-e3d53ec6aa1e.png)</MultiModal>

When the water molecule attacks from below, the degree of conformational change of the system is minimal, and the reaction energy barrier is low.

<Checkpoint>[When the water molecule attacks from below, the degree of conformational change of the system is minimal, and the reaction energy barrier is low.](1)</Checkpoint>

Therefore, the main reaction product finally obtained by hydrolysis of $\mathbf{A}$ is

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/dc00a6a0-f8ad-4c2c-849a-a93ab5ccd96a.png)</MultiModal>

<Checkpoint>[Final hydrolysis product: [H][C@@]12[C@](CCCC2)([H])[C@H](O)[C@H](O)C3=CC=C(OC)C=C31](1)</Checkpoint>
甲氧基具有一定的的共轭给电子效应，可以稳定苄位的碳正离子

<Checkpoint>[甲氧基具有一定的的共轭给电子效应，可以稳定苄位的碳正离子](1)</Checkpoint>

因此首先三元环在酸性条件下发生开环形成碳正离子中间体1

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@](O)([H])[C+]([H])C3=CC=C(OC)C=C31](/media/uploads/ba83be3a-3353-4889-a87c-a982148c2394.png)</MultiModal>

<Checkpoint>[[H][C@@]12[C@](CCCC2)([H])[C@@](O)([H])[C+]([H])C3=CC=C(OC)C=C31](1)</Checkpoint>

该中间体的构象为

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@](O)([H])[C+]([H])C3=CC=C(OC)C=C31](/media/uploads/49c4a440-8f00-4779-97a9-6ed4a5368bee.png)</MultiModal>

可以画出其发生$\mathrm{H_2O}$亲核进攻时的纽曼投影式

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@@](O)([H])[C+]([H])C3=CC=C(OC)C=C31](/media/uploads/b5d8d3ad-796e-42a7-8f3e-e3d53ec6aa1e.png)</MultiModal>

当水分子从下方进攻时，体系构象改变程度最小，反应能垒较低

<Checkpoint>[当水分子从下方进攻时，体系构象改变程度最小，反应能垒较低](1)</Checkpoint>

因此$\mathbf{A}$水解最终得到的主要反应产物为

<MultiModal>![[H][C@@]12[C@](CCCC2)([H])[C@H](O)[C@H](O)C3=CC=C(OC)C=C31](/media/uploads/dc00a6a0-f8ad-4c2c-849a-a93ab5ccd96a.png)</MultiModal>

<Checkpoint>[最终水解产物：[H][C@@]12[C@](CCCC2)([H])[C@H](O)[C@H](O)C3=CC=C(OC)C=C31](1)</Checkpoint>