Javascript click button1

Hi i have the following html code, and i'm truing to make a javascript to click on this button

<fieldset class="fields1"></fieldset>
<fieldset class="submit-buttons">
<some other button here >
<input class="button1" type="submit" value="Submit" name="post" tabindex="4" accesskey="f"></input>

What i already tried is the following options,

$(".submit-buttons").children('input[name="post"]').click();

doesn't work

and this way also, and this doesn't work neither

$("input[name=post]").click();

Is there any other way to click the button1, or is any way i can select tabindex4 or accesskey f, as these are values that wont change?, the problem is that i don't have any id button.

Thanks