A certain Chevron-shaped four-armed monomer structure is as follows:
<MultiModal>![[R]OC(C(C#C[R2])=C1)=C(C#C[R2])C=C1C#CC(C=C2)=CC=C2N(C3=CC=C(C=C3)C#CC4=CC(C#C[R1])=CC(O[R])=C4)C(C=C5)=CC=C5C#CC6=CC(O[R])=CC(C#C[R1])=C6](/media/uploads/aabf2147-fabd-4ef8-80d1-78dbceee978c.png)</MultiModal>

Let $\rm R_1=TIPS$, $\rm R_2=H$, the monomer is denoted as $\bf M1$; when $\rm R_1=H$, $\rm R_2=TIPS$, the monomer is denoted as $\bf M2$; when $\rm R_1=TIPS$, $\rm R_2=Pt(PEt_3)_2I$, the monomer is denoted as $\bf M3$; when $\rm R_1=H$, $\rm R_2=H$, the monomer is denoted as $\bf M4$.

When $\rm R_1$ and $\rm R_2$ are different, the four-armed monomer can undergo polymerization to obtain polymers (or oligomers) $\bf A$~$\bf D$ with different structures:

<MultiModal>![The figure shows the reactions for synthesizing $\bf A$, $\bf B$, $\bf C$ to $\bf D$, respectively.
1. $0.5 mM$ $\bf M1$ reacts under $trans-Pt(PEt_3)_2I_2, cat. CuI$ conditions to obtain intermediate $\bf A1$, continues to react under $TBAF$ conditions to obtain intermediate $\bf A2$, and continues to react under $trans-Pt(PEt_3)_2I_2$ conditions to obtain $\bf A$.
2. $10 mM$ $\bf M1$ reacts under $trans-Pt(PEt_3)_2I_2, cat. CuI$ conditions to obtain intermediate $\bf B1$, continues to react under $TBAF$ conditions to obtain intermediate $\bf B2$, and continues to react under $trans-Pt(PEt_3)_2I_2$ conditions to obtain $\bf B$.
3. $10 mM$ $\bf M2$+$10 mM$ $\bf M3$ reacts under $\bf M2:M2$ $=1:1, cat. CuI$ conditions to obtain intermediate $\bf C1$, continues to react under $TBAF$ conditions to obtain intermediate $\bf C2$, and continues to react under $trans-Pt(PEt_3)_2I_2$ conditions to obtain $\bf C$.
4. $10 mM$ $\bf M4$ reacts under $trans-Pt(PEt_3)_2I_2, cat. CuI$ conditions to obtain $\bf D$.](/media/uploads/483c5450-bdf3-4918-bbf4-ac1e5248fa62.png)</MultiModal>

It is known that $\bf A$~$\bf D$ can be regarded as 1) a cyclic structure 2) a network structure 3) a one-dimensional helical chain 4) a one-dimensional linear chain, respectively. Please correspond them one by one and represent them with a four-digit number (e.g., if $\bf A$ corresponds to 1), $\bf B$ corresponds to 2), $\bf C$ corresponds to 3), and $\bf D$ corresponds to 4), then it is represented as 1234).
某Chevron形状的四臂单体结构如下：
<MultiModal>![[R]OC(C(C#C[R2])=C1)=C(C#C[R2])C=C1C#CC(C=C2)=CC=C2N(C3=CC=C(C=C3)C#CC4=CC(C#C[R1])=CC(O[R])=C4)C(C=C5)=CC=C5C#CC6=CC(O[R])=CC(C#C[R1])=C6](/media/uploads/aabf2147-fabd-4ef8-80d1-78dbceee978c.png)</MultiModal>

记$\rm R_1=TIPS$、$\rm R_2=H$时单体为$\bf M1$；$\rm R_1=H$、$\rm R_2=TIPS$时单体为$\bf M2$；$\rm R_1=TIPS$、$\rm R_2=Pt(PEt_3)_2I$时单体为$\bf M3$；$\rm R_1=H$、$\rm R_2=H$时单体为$\bf M4$。

当$\rm R_1$和$\rm R_2$不同时，该四臂单体可以发生聚合得到不同结构的聚合物（或寡聚物）$\bf A$~$\bf D$：

<MultiModal>![图中分别为合成$\bf A$、$\bf B$、$\bf C$至$\bf D$的反应。
1. $0.5 mM$ $\bf M1$在$trans-Pt(PEt_3)_2I_2, cat. CuI$条件下反应得到中间体$\bf A1$，继续在$TBAF$条件下反应得到中间体$\bf A2$，继续在$trans-Pt(PEt_3)_2I_2$条件下反应得到$\bf A$。
2. $10 mM$ $\bf M1$在$trans-Pt(PEt_3)_2I_2, cat. CuI$条件下反应得到中间体$\bf B1$，继续在$TBAF$条件下反应得到中间体$\bf B2$，继续在$trans-Pt(PEt_3)_2I_2$条件下反应得到$\bf B$。
3. $10 mM$ $\bf M2$+$10 mM$ $\bf M3$在$\bf M2:M2$ $=1:1, cat. CuI$条件下反应得到中间体$\bf C1$，继续在$TBAF$条件下反应得到中间体$\bf C2$，继续在$trans-Pt(PEt_3)_2I_2$条件下反应得到$\bf C$。
4. $10 mM$ $\bf M4$在$trans-Pt(PEt_3)_2I_2, cat. CuI$条件下反应得到$\bf D$。](/media/uploads/483c5450-bdf3-4918-bbf4-ac1e5248fa62.png)</MultiModal>

已知$\bf A$~$\bf D$可以分别看作1)环状结构 2)网状结构 3)一维螺旋状链 4)一维直线型链，请将其一一对应并用一个四位数表示（如$\bf A$对应1)，$\bf B$对应2)，$\bf C$对应3)，$\bf D$对应4)则表示为1234）。
All other options are incorrect
1,2,3,4
1,4,2,3
3,1,2,4
1,3,4,2
4,1,2,3
2,4,3,1
2,1,3,4
2,3,1,4
3,2,4,1
3,4,1,2
4,3,2,1
4,2,3,1
其他选项均不正确
1,2,3,4
1,4,2,3
3,1,2,4
1,3,4,2
4,1,2,3
2,4,3,1
2,1,3,4
2,3,1,4
3,2,4,1
3,4,1,2
4,3,2,1
4,2,3,1
If the alkyne terminus is hydrogen, it can react with $\rm trans-Pt(PEt_3)_2I_2$ under $\rm CuI$ catalysis to lose HI, polymerizing the monomer $\bf M$ with a $\rm trans~C-Pt-C$ bond (linear).

<Checkpoint>[The alkyne of $\bf M$ can achieve polymerization via linear coordination to $\rm Pt$](1)</Checkpoint>

For $\bf M1$, the first polymerization reaction occurs at the lower alkyne. After TBAF removes the TIPS group, the upper alkyne can continue to react later. Aligning the upper and lower alkynes, it can be found that six $\bf M1$ can undergo two rounds of polymerization, inner and outer, to obtain a hexamer similar to hexabenzene, i.e., 1) cyclic structure; if multiple $\bf M1$ participate in the polymerization in the first step, it will extend in a helical form, i.e., 3) one-dimensional helical chain.

<Checkpoint>[$\bf M1$ can be polymerized to obtain 1) and 3)](1)</Checkpoint>

When the concentration of $\bf M1$ is low (0.5 mM), the probability of intramolecular polymerization to form a closed loop is relatively higher, which is conducive to the formation of 1) cyclic structure $\bf A$; when the concentration of $\bf M1$ is high (10 mM), intermolecular polymerization reactions are more dominant, which is conducive to monomers connecting one by one to form 3) one-dimensional helical chain $\bf B$.

<Checkpoint>[At higher concentrations, intermolecular reactions are more likely to occur，$\bf A$ corresponds to 1)，$\bf B$ corresponds to 3)](1)</Checkpoint>

After alternating copolymerization of $\bf M2$ and $\bf M3$, a six-membered ring can be formed, and the formed polymer chain extends macroscopically into a 4) one-dimensional linear chain.

<Checkpoint>[$\bf C$ corresponds to 4)](1)</Checkpoint>

All four alkynes of $\bf M4$ are reactive and can participate in polymerization together, without directionality, thus obtaining a network $\bf D$.

<Checkpoint>[$\bf D$ corresponds to 2)](1)</Checkpoint>
若炔基末端为氢，则可以在$\rm CuI$催化下与$\rm trans-Pt(PEt_3)_2I_2$反应失去HI，以$\rm trans~C-Pt-C$键（直线型）将单体$\bf M$聚合起来。

<Checkpoint>[$\bf M$的炔基可以对$\rm Pt$直线型配位实现聚合](1)</Checkpoint>

对于$\bf M1$，第一步聚合反应发生在下方的炔基，TBAF脱去TIPS基团后上方的炔基才能之后继续反应。上下炔基对齐可以发现，6个$\bf M1$恰好可以经历内外两圈的两次聚合得到类似并六苯的六聚体，即1)环状结构；而第一步反应若有多个$\bf M1$参与聚合，则会以螺旋的形式延伸下去，即3)一维螺旋状链。

<Checkpoint>[$\bf M1$可以聚合得到1)和3)](1)</Checkpoint>

当$\bf M1$浓度较低（0.5 mM）时，分子内聚合形成闭环的概率相对更高，有利于生成1)环状结构$\bf A$；当$\bf M1$浓度较高（10 mM）时，分子间聚合反应更占优势，有利于单体逐个连接形成3)一维螺旋状链$\bf B$

<Checkpoint>[浓度更高时，更容易发生分子间反应，$\bf A$对应1)，$\bf B$对应3)](1)</Checkpoint>


$\bf M2$和$\bf M3$交替共聚后可以形成六元环，形成的聚合物链在宏观上延伸为4)一维直线型链

<Checkpoint>[$\bf C$对应4)](1)</Checkpoint>

$\bf M4$的四个炔基均有反应活性，可以一起参与聚合，不具有方向性，因此得到网状的$\bf D$

<Checkpoint>[$\bf D$对应2)](1)</Checkpoint>