<div class="container_row">
  <div class="rect large"></div>
  <div class="rect short"></div>
  <div class="container_col">
    <div class="square"></div>
    <div class="rect short"></div>
    <div class="rect short"></div>
    <div class="rect short"></div>
    <div class="rect short"></div>
  </div>
</div>

.container_row,
.container_col {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-content: space-between;
  width: 760px;
}

.container_row {
  height: 370px;
}

.container_col {
  flex-direction: column;
  height: 240px;
}

.rect, 
.square {
  background-color: #2e2e2e;
}

.rect {
  height: 110px;
}

.large {
  width: 500px;
}

.short {
  width: 240px;
}

.square {
  width: 240px;
  height: 240px;
}