"IndexError: tuple index out of range" error with numpy array contain datetimes
#### Code Sample, a copy-pastable example if possible

```python
>>> from datetime import datetime as dt
>>> import numpy as np
>>> from pandas import DataFrame
>>> d=np.array([None, None, None, None, dt.now(), None])
>>> b = DataFrame(d)

```
#### Problem description

The above code works in an old version of pandas (0.7.3) but fails in the current version (0.19.2)

#### Expected Output
No error and dataframe containing the numpy date array
#### Output of ``pd.show_versions()``

<details>
>>> pandas.show_versions()
INSTALLED VERSIONS
------------------
commit: None
python: 2.7.12.final.0
python-bits: 64
OS: Windows
OS-release: 10
machine: AMD64
processor: Intel64 Family 6 Model 26 Stepping 5, GenuineIntel
byteorder: little
LC_ALL: None
LANG: None
LOCALE: None.None

pandas: 0.19.2
nose: None
pip: 9.0.1
setuptools: 20.10.1
Cython: None
numpy: 1.12.1
scipy: None
statsmodels: None
xarray: None
IPython: None
sphinx: None
patsy: None
dateutil: 2.6.0
pytz: 2017.2
blosc: None
bottleneck: None
tables: None
numexpr: None
matplotlib: None
openpyxl: None
xlrd: None
xlwt: None
xlsxwriter: None
lxml: None
bs4: None
html5lib: None
httplib2: None
apiclient: None
sqlalchemy: None
pymysql: None
psycopg2: None
jinja2: None
boto: None
pandas_datareader: None
>>>
</details>
