array.php

<?php

$social_data = [
    [
        'first' => 'John',
        'middle' => 'Smith',
        'last' => 'Doe',
        'email' => 'abc@example.com'
    ],
    [
        'first' => 'John',
        'last' => 'Doe',
        'email' => 'abc@example.com'
    ],
    [
        'first' => 'John',
        'last' => 'Doe',
    ]
];

$new = [];

foreach ($social_data AS $d)
{
	$new[] = [
		'full_name' => $d['first'] . ' ' . $d['middle'] . ' ' . $d['last'],
		'email_address' => $d['email']
	];
}