Uncaught+TypeError:+Cannot+read+property+'execute'+of+undefined

When trying to call a apex class on button click on skuid by running javascript snippet getting ‘Uncaught TypeError: Cannot read property ‘execute’ of undefined’

Uncaught TypeError: Cannot read property ‘execute’ of undefined(anonymous function)
@ skuid__ui?page=VINDecoding:116
k.custom @ skuid__SkuidJS:32
f.runActionNode @ skuid__SkuidJS:32
m @ skuid__SkuidJS:32
f.runActionsNode @ skuid__SkuidJS:32
i @ runtime.js:4
o.event.dispatch @ skuid__JQuery:3
r.handle @ skuid__JQuery:3

This is code of my snippet

var params = arguments[0], $ = skuid.$;

var vinJSON = {
vinnumber: “2G1FC3D33C9165616”
};
var result = sforce.apex.execute(“GetVIN”,“getVINDETAILS”,{ dispatchJSON: JSON.stringify(vinJSON) });
console.log('the result was: ’ + result);

I have added ajax toolkit