Compounds and uses thereof

A compound having the structure of Formula I:

• wherein
• X is halo;
• X1 is absent, O, or NR1;
• k is 0, 1, 2, or 3;
• n is 0, 1, or 2;
• R1 is H or optionally substituted C1-C6 alkyl;
• L1 is optionally substituted C1-C6 alkylene, optionally substituted C2-C6 alkenylene, or optionally substituted C2-C6 alkynylene;
• L2 is absent, optionally substituted C1-C6 alkylene, optionally substituted C1-C20 heteroalkylene, or optionally substituted C2-C9 heterocyclylene;
• each L3 is, independently, optionally substituted C1-C20 heteroalkylene, optionally substituted C3-C10 carbocyclylene, optionally substituted C3-C10 carbocyclylene-C1-C6 alkylene, optionally substituted C2-C9 heterocyclylene, optionally substituted C2-C9 heterocyclylene-C1-C6 alkylene, optionally substituted C6-C10 arylene, optionally substituted C6-C10 arylene-C1-C6 alkylene, optionally substituted C2-C6 alkynylene, O, or NR1;
• and
• D is a degradation moiety,
• or a pharmaceutically acceptable salt thereof.