Ivan Brezhnev

<button
  type="button"
  class="btn btn-primary"
  (click)="panels.panel1 = !panels.panel1"
  [attr.aria-expanded]="!panels.panel1"
  aria-controls="collapseBasic1"
>
  Toggle collapse
</button>

<hr />

<div id="collapseBasic1" [collapse]="panels.panel1">
  <div class="well well-lg card card-block card-header">Some content</div>
</div>

<button
  type="button"
  class="btn btn-primary"
  (click)="panels.panel2 = !panels.panel2"
  [attr.aria-expanded]="!panels.panel2"
  aria-controls="collapseBasic1"
>
  Toggle collapse
</button>

<hr />

<div id="collapseBasic1" [collapse]="panels.panel2">
  <div class="well well-lg card card-block card-header">Some content</div>
</div>

// panels.component.ts
export class PanelsComponent {
  public panels: { [panelName: string]: boolean } = {
    panel1: false,
    panel2: false
  }
}