<mat-checkbox  [(ngModel)]="element[column]" (click)="updateRow(element, $event)"></mat-checkbox>

updateRow(row, $event): void {
    Observable.from([{ row: row }])
      .concatMap(i => this._definitionService.updateDefinition(i)  //async work
      .subscribe(result => console.log('row updated'), error => {
        this.snack(error);
      });
  }

Observable.fromEvent($event.target, 'click')
              .subscribe(i => {
                console.log(i);
              });