Trying to use boost::serialization of Boost::any - c++

Question

I am trying to work with boost::serialisation for saving and loading some objects.
So far from the boost::tutorial I have managed to do things work for all the different stl stuff (vectors, pairs, lists etc), for derived classes, for boost multi-arrays and other things, but I am stuck trying to work around how to serialize a boost::any vector.
Let me say in advance that I found and checked in the forum some posts for boost::varian serialization and even one for boost::any (which even has an almost identical title) but yet again I didn't manage to solve my problems.
So let me go with a small example:
Say I have this class:
class class_2
{
private:
template<class Archive>
void serialize(Archive & ar, const unsigned int version)
{
ar & degrees;
ar & minutes;
ar & seconds;
for( std::vector<boost::any>::iterator it = v_any.begin() ; it != v_any.end() ; ++it ) {
//Trying to cast all the possible types that may enter the
//boost any vector, for the sake of this example let's just
//say that we will only pass a second class called name class_1
//to the boost::any vector and we only have to cast this class
if (it->type() == typeid(class_1)){
class_1 lan = boost::any_cast< class_1 > (*it );
ar & (lan);
}
}// for boost::any*/
} //serialization
public:
int degrees;
int minutes;
float seconds;
class_2(){};
class_2(int d, int m, float s) :
degrees(d), minutes(m), seconds(s)
{}
std::vector<boost::any> v_any;
};
And to be more precise the class_1 that we expect for this small example to exist inside the boost::any vector is the following class:
class class_1
{
private:
friend class boost::serialization::access;
template<class Archive>
void serialize(Archive & ar, const unsigned int version)
{
ar & a;
}
public:
class_1(){};
int a;
};
So when I compile the above code with a main function where I save and load an object of class_2 that containts inside the boost::any vector an object of class_1 everything compiles and even runs:
int main() {
class_1 alpha;
class_2 beta;
alpha.a=5;
beta.v_any.push_back(alpha);
std::ofstream ofs("file");
// save data to archive
{
boost::archive::text_oarchive oa(ofs);
// write class instance to archive
oa << beta;
// archive and stream closed when destructors are called
}
// ... some time later restore the class instance to its orginal state
class_2 newclass;
{
// create and open an archive for input
std::ifstream ifs("file");
boost::archive::text_iarchive ia(ifs);
// read class state from archive
ia >> newclass;
// archive and stream closed when destructors are called
}
return 0;
}
Yet again the loaded newclass object has an empty boost::any vector with nothing saved inside.
So my question is what am I doing wrong in the above code and what should I change in order to serialize the boost::any vector correctly..?
Any help/suggestion would be very appreciated.