List Entries and Matrix
You'll have to build a list of the data and then display it.

{% set arr = [] %}

{% for coupon in craft.entries.section('coupons').status('live').order('postDate asc') %}
    {% for content in coupon.contentBuilder %}
        {% set arr = arr|merge([content.myUniqueFieldName: content]) %}
    {% endfor %}
{% endfor %}

{% for item in arr %}
    {{ item.title }}
{% endfor %}